The Project Gutenberg EBook of The Common Spiders of the United States, by James Henry Emerton This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org Title: The Common Spiders of the United States Author: James Henry Emerton Release Date: April 22, 2013 [EBook #42576] Language: English Character set encoding: ISO-8859-1 *** START OF THIS PROJECT GUTENBERG EBOOK COMMON SPIDERS OF THE U.S. *** Produced by Bryan Ness, Susan Theresa Morin, Sharon Joiner, TIA: American Libraries and the Online Distributed Proofreading Team at http://www.pgdp.net (This book was produced from scanned images of public domain material from the Google Print project.) See Transcriber's Notes at end of index. THE COMMON SPIDERS OF THE UNITED STATES By JAMES H. EMERTON Boston, U.S.A., and London GINN & COMPANY, PUBLISHERS The Athenæum Press Entered at Stationers' Hall Copyright, 1902, by JAMES H. EMERTON ALL RIGHTS RESERVED 24.12 PREFACE There are few books on the American spiders, and these are either large and expensive works or else special papers published by scientific societies, and so little known to the public. Since publishing my papers on the New England and Canadian spiders in the Transactions of the Connecticut Academy from 1882 to 1894, I have had frequent calls for a smaller and simpler book to meet the wants of readers who, without making a special study of the subject, want to [Pg iii] know a little about spiders in general and especially those species that they often meet with. It is hoped this book will answer the purpose and help to lessen the prejudice against spiders, and lead to a more general acquaintance with them, like the popular knowledge of birds and butterflies. The characters used in the descriptions are, as far as possible, those that can be seen without microscopic examination and without much experience in the handling of small animals. The illustrations, which show the form and markings of every species, are from my own drawings and photographs, a large part of them made new for this book. J. H. EMERTON. April, 1902. CONTENTS Introduction Page Number and Names of Spiders vii Anatomy viii Silk and Spinning Organs x Colors and Markings xi Habitats of Common Spiders xii-xiv Cobwebs xvi Catching and Preserving Spiders xvii The Drassidæ 1-21 Clubiona 15 The Dysderidæ 22 The Thomisidæ 24-40 Misumena 25 Xysticus 30 Philodromus 35 The Attidæ 41-66 The Lycosidæ 67-90 Lycosa 68 Pardosa 78 Dolomedes 85 Ocyale 88 Oxyopes 88 The Agalenidæ 91-106 The Therididæ 107-133 Theridium 110 Steatoda 119 Pholcus 128 Scytodes 131 The Linyphiadæ 134-153 Linyphia 134 Erigone 148 The Epeiridæ 154-204 Round Webs of the Epeiridæ 155-159 Species of Epeira 160-181 The Three Species of the Genus Zilla 184 Acrosoma 188 [Pg v][Pg vi] Argiope 192-198 Tetragnatha 198-204 The Ciniflonidæ, or Cribellata 205-220 Dictyna 205 Amaurobius 213 Uloborus 216 Hyptiotes 218 Filistata 220 INTRODUCTION This book is designed to make the reader acquainted with the common spiders most likely to be found over a large part of the United States as far south as Georgia and as far west as the Rocky Mountains. Local collections show that in the neighborhood of any city in the country there are at least three or four hundred species of spiders; but few such collections have been made, and it is not yet possible to tell all the kinds of spiders that live in any particular place, or how far any species extends over the country. The species which are here described and figured are all of them well known and have been described in other books. Rare and doubtful species are omitted, though some of these may in time prove to be among the most common. A large number of spiders are too small to be easily seen, and most of these are omitted, only a few representative species being described. Spiders have, unfortunately, no common names, except such indefinite ones as "the garden spider," "the black spider," "the jumping spider," and the like. Even "tarantula" has become only a nickname for any large spider. The names of spiders, like those of other animals, have been given to them independently by different persons, so that many of them have more than one name, and the more common the spider the larger the number of names. In this book only one name is usually given to each species, and the name used is one that has been published with a description of the species in some other well-known book. Readers who are interested in the names of species and in comparing the classifications of different naturalists are referred to a "Catalogue of the Described Araneæ Of Temperate North America," by George Marx, in the Proceedings of the United States National Museum, 1890, which is a useful index to what has been published on American spiders. The front half of a spider's body, called the cephalothorax, contains in one piece the head and thorax, the only outward division between them being shallow grooves from the middle of the back to the front legs. In the middle of the cephalothorax is usually a groove or depression, under which, inside, is a muscle that moves the sucking apparatus by which food is drawn into the mouth. At the sides of the thoracic part are four pairs of legs, and on the head part are a pair of palpi and a pair of mandibles. The legs have seven joints: (1) the coxa, the thick basal joint, having little motion; (2) the trochanter, a short joint moving very freely on the end of the coxa; (3) the femur, the largest joint of the leg, moving with the trochanter in all directions; (4) the patella, moving up and down on the end of the femur; (5) the tibia, joined closely to the patella and moving with it up and down; (6) the metatarsus; and (7) the tarsus, moving together on the end of the tibia. The palpi are like small legs and have one less joint than the walking legs. The mandibles are close together at the front of the head (fig. 2). They are two-jointed, the basal joint stout and the end joint or claw slender and sharp-pointed. The claw has near its point a small hole, which is the outlet of the poison gland. The poison kills or disables the insects which are captured by the spider. Its effect on the human skin varies in different persons; sometimes it has no effect at all; oftener it causes some soreness and itching like the stings of mosquitoes and bees, and cases have been known in which it caused serious inflammation which lasted a long time. Spiders seldom bite, and only in defense, the bites so commonly charged to them being often the work of other animals. FIG. 1. Diagram of the under side of a spider, with the [Pg vii] [Pg viii] [Pg ix] legs removed except one. FIG. 2. Front of head, showing the eyes and mandibles. On the front of the head are the eyes, usually eight in number, differing in size and arrangement according to the kind of spider. The sight of spiders is distinct for only short distances. Spiders of middle size can see each other, and the insects which they eat, at a distance of four or five inches, but beyond that do not seem to see anything clearly. At the ends of the feet are two claws, curved and with teeth along the inner edge, and in many spiders there is a third shorter claw between them (fig. 212). The claws are sometimes surrounded by a brush of flattened hairs (figs. 104, 114). The basal joints of the palpi are flattened and have their inner edges extended forward so that they can be used as jaws to press or chew the food. These are called the maxillæ. Between the maxillæ is a small piece called the labium, and between the legs is a larger oval piece called the sternum. The hinder half of the body, the abdomen, is connected with the cephalothorax by a narrow stem (fig. 1). It has at the hinder end the spinnerets, three pairs of appendages having at their ends a great number of microscopic tubes through which the thread is drawn out. When not in use the spinnerets are folded together, so that the smaller inner pair are concealed. The thread of spiders resembles that spun by caterpillars in making their cocoons, and can be manufactured in the same way into silk cloth. The spider's thread is composed of a great number of finer threads passing from the body through separate tubes and uniting into one before they have time to dry. This can be seen by examining the attachments of spiders' threads to glass. All the spinning tubes are not alike, but on certain parts of the spinnerets are larger or differently shaped tubes, and these are the outlets of glands of different kinds in the spider's abdomen, and are used in making different kinds of threads for certain parts of the webs, nests, or cocoons. In front of the spinnerets on the under side is a small opening to the tracheæ, or air-tubes (fig. 1). At the front of the abdomen on the under side is a transverse fold of the skin, at the ends of which are the openings of the air-sacs or lungs, and between them the opening of the reproductive organs (fig. 1). The latter is covered in females by an apparatus, sometimes large and complicated, called the epigynum. Its presence shows that the female is full grown. Young spiders do not have it. Male spiders have the ends of the palpi enlarged, and under the terminal joint what is known as the palpal organ, sometimes very complicated in shape. The presence of these organs shows that the male is full grown. Young males that have nearly reached maturity have the ends of the palpi simply enlarged. Male spiders almost always have the body smaller and the legs longer than females of the same species. The colors of spiders are partly in the skin itself and partly in the hairs and scales that cover it. Almost all spiders are covered with hair of some kind, but in some species it is so fine and short that it has little effect on the color. In others the skin is entirely covered with hairs of various lengths and sometimes with scales somewhat like those of butterflies, flattened and feathered or toothed on the edges. The colors of spiders are very varied, and in many species, especially of the jumping spiders, as brilliant as those of butterflies. The most common colors are grays and browns, resembling the ground or plants and stones among which the spiders live. Sometimes the color is uniform all over the body, except that it is a little darker toward the head and the ends of the feet. The most common marking is a spot on the front of the abdomen over the spider's heart, sometimes merely a translucent part of the skin and sometimes a definite color spot darker in the middle and outlined with a lighter shade or white. The hinder half of the abdomen is often marked with several pairs of spots, becoming smaller toward the end, and these spots may be united into a pair of stripes or a more complicated pattern. (See figures.) The legs are often marked with rings of color, almost always at the ends of the joints. Besides these common markings there are in some spiders strong contrasts of color, such as bright red or yellow spots on a black ground. In the males, especially among the Attidæ, there are often shining scales that reflect different colors in a bright light, and tufts of black or white hairs about the head and front legs. Spiders live in all kinds of places. Certain species are attached to houses and seldom found far from them, and many of these occur over a large part of the world. The light webs in the corners of rooms are chiefly the work of Theridium tepidariorum (p. 112), occasionally of Steatoda borealis (p. 119) and Steatoda triangulosa (p. 121). In cellars the thin webs about the stairs and shelves are those of the long-legged Pholcus phalangioides (p. 129) or of Linyphia nebulosa or minuta (pp. 144, 145), and the thick flat webs in corners and between the beams are those of Tegenaria derhamii (p. 96). On the outside of houses live two jumping spiders, the most common being Epiblemum scenicum (p. 60), a small gray species the color of weathered wood, and the other, Marptusa familiaris (p. 61). Some of the round-web spiders live in great numbers about houses. The three brown species, Epeira sclopetaria (p. 160), patagiata, and strix, hide in cracks and at night make their round webs in porches, barns, and bridges. In the northern part of the country Epeira cinerea (p. 165) has the same habit. Epeira globosa (p. 174) is often found on the outside of houses, and so are Zilla atrica and Zilla x-notata (p. 185). Amaurobius ferox (p. 215), a large imported species, is sometimes found in cellars, and several Dictyna (p. 206) live in great numbers on the outside of houses, in corners of windows, under the edges of shingles, or in cracks of walls, spreading their webs wherever there is room for them and gathering dust so that they often make a distinct spot on the wall. In the southern states Filistata hibernalis (p. 220) is one of the most common spiders about houses. Its webs often make a round spot of dust a foot or more in diameter. Stones and sticks lying on the ground furnish shelter for a great number of spiders. Steatoda borealis (p. 119), marmorata (p. 121), and guttata (p. 120) and Asagena americana (p. 122) are found in such places, and so, especially in the South, is Latrodectus mactans (p. 122). The large jumping spiders, Phidippus mystaceus (p. 50) and tripunctatus (p. 51), make large nests of white silk under stones near the ground. The ground spiders, Drassus saccatus (p. 6), Gnaphosa conspersa (p. 2), and Prosthesima atra (p. 5), run on the ground and hide under stones. Lycosa nidicola (p. 69), Lycosa communis (p. 75), Lycosa pratensis (p. 69), polita (p. 70), and cinerea (p. 74) are [Pg x] [Pg xi] [Pg xii] [Pg xiii] often found under shelters of this kind. The crab spiders of the genus Xysticus live under stones, but oftener under bark farther from the ground. In the summer, plants of all kinds from grass to trees are full of spiders. The Lycosas (pp. 68 to 84)run among the short grass. The small species of Linyphia (p. 134) and Erigone (p. 148) make their flat webs close to the ground among small plants. Linyphia marginata, communis, coccinea, and phrygiana make theirs among plants and rocks, a foot or two above the ground. The Theridiums (p. 110) live between leaves and on the ends of twigs, covering them with webs that only show when the dew is on them. Agalena nævia (pp. 91 to 95) makes its flat webs on the grass and anywhere else where it can find a place to fasten them. The jumping spiders (p. 41) run about for their prey on plants, and some of them have silk nests among the leaves. The Misumenas (p. 25) live among flowers and wait for insects to alight within reach. The webs of Dictyna (p. 206) are commonest on the ends of grass and twigs, and are known by the dust that they gather. The round-web spiders mature in the middle of the summer, and then Epeira trivittata (p. 166) is found on all kinds of bushes and grass, and later Epeira insularis (p. 169) and Epeira trifolium (p. 171) in hidden nests near their webs. Epeira angulata, sylvatica, and nordmanni (p. 162) live among bushes and trees. Cyclosa conica (p. 183), Acrosoma spinea (p. 190), and Uloborus (p. 216) live among low bushes in openings of the woods. Hyptiotes (p. 218) lives among the lower dead branches of pines, perching on the end of a twig which it exactly matches in color. The marshes are the home of great numbers of spiders. The Tetragnathas (p. 198) live there, especially along the streams and ditches. Epeira gibberosa (p. 175) and placida (p. 176) make their horizontal and oblique webs among the tall grass in open places. The two species of Argiope (pp. 193 to 198) swarm in marshes and open fields and in autumn become conspicuous by their size and bright colors, and when they disappear leave over winter their brown cocoons (pp. 197, 200) fastened to the grass. The moss and dead leaves in the woods are alive with spiders; even in summer some species always live there, and in winter the young of those that in warm weather live among the bushes find shelter where they can remain torpid through the cold season without freezing. The eggs of spiders are covered with silk, forming a cocoon which varies much in shape and color in different species. Some spiders hang it in the web, others attach it to plants or stones, and others carry it about with them either in the mandibles or attached behind to the spinnerets. The young remain in the cocoon until they are able to run about, and after coming out of the cocoon keep together for a short time, sometimes in a web which they make in common, sometimes in a nest made by the mother, and in some species on the mother's back, but they soon scatter and hunt their own food or make cobwebs, according to the habits of the species. Different kinds of spiders mature and breed at different times of the year, most of them living only one season. Those that mature late, like Agalena nævia and Argiope, pass the winter as eggs, while those that mature early, like Epeira sclopetaria and Lycosa nidicola, pass the winter half grown. Some species, like Theridium tepidariorum (p. 112), breed several times in the year, and old and young are found at all seasons. The spiders are naturally divided into two groups of families: (1) the hunting spiders, which run on the ground or on plants, catching insects wherever they find them, or waiting among leaves and flowers until insects come within their reach; (2) the cobweb spiders, which make webs to catch insects and live all the time in the web or in a nest near it. The hunting spiders include: (1) the Dysderidæ (p. 22), a few species with six eyes only and with four breathing holes at the front end of the abdomen; (2) the Drassidæ (p. 1), or ground spiders, which live among stones and dead leaves or among plants, making tubular nests and flat egg cocoons but no cobwebs; (3) the Thomisidæ (p. 24), the flat and crab- like spiders living on plants or under bark and stones; (4) the Attidæ (p. 41), the jumping spiders, with wide heads and large front eyes, many of them brightly colored and active in their habits; (5) the Lycosidæ (p. 67), the long-legged running spiders, living on the ground and, a few of them, in holes and carrying about their round egg cocoons attached to the spinnerets. The cobweb spiders include: (1) the Agalenidæ (p. 91, making flat webs on grass or in corners of houses, with a tube at one side in which the spider lives; (2) the Therididæ (p. 107), round spiders with flat or irregular webs in corners and on plants; (3) the Linyphiadæ (p. 134), with flat webs, small spiders of a great number of species living near the ground and in shady places; (4) the Epeiridæ (p. 154), the round web spiders; (5) the Cribellata, having a calamistrum (see p. 205) on the hind legs and making rough webs that gather dust. Cobwebs are of four principal kinds: 1. The flat webs, closely woven of long threads crossed by finer ones in all directions and connected with a tubular nest where the spider hides, and from which it runs out on the upper side of the web after insects that may fall upon it. These are made by Agalena and Tegenaria (pp. 91 to 104). 2. The net-like webs, made of smooth threads in large meshes, sometimes in a flat or curved sheet held out by threads in all directions. The spider lives on the under side, back downward. These are made by Therididæ and Linyphiadæ (pp. 107, 134). 3. The round webs, made of threads radiating from a common center and crossed by circular loops and spirals, part of which are adhesive. 4. The webs of the Ciniflonidæ, composed in part of loose bands of silk (p. 205). [Pg xiv] [Pg xv] [Pg xvi] The simplest and best way to preserve spiders for examination is to put them in alcohol. It kills them immediately and keeps their form and markings and, to a great extent, their colors. They may be kept alive for a few days in glass bottles or jars. It is not necessary to make holes in the covers, or to feed the spiders often. They need water, and this can be furnished them conveniently by putting a piece of wet paper or rag in the bottle. If one wishes to find what spiders live in his neighborhood, they must be looked for at all times and in all kinds of places. The house and cellar should be looked over and the spiders watched until they are fully grown. The outside of the house and fences should be looked over occasionally in the same way, only those spiders being taken that are full grown, unless they are of new or rare kinds. A great many spiders may be found on the garden fences of a shady street, especially in the early summer and again in the autumn. At both seasons they are more active in the middle of the day and more likely then to be wandering about. The writer always carries two small bottles, one a common homeopathic medicine vial, holding one or two drams and half full of alcohol, the other a straight tube vial, without any neck and about the same size, that is kept always dry and occasionally wiped out to remove the threads that are made in it. The dry bottle is placed quickly over the spider and moved about until the spider is coaxed to go into it. The bottle is then turned up and closed with a finger until the other bottle can be uncorked and the spider shaken into the alcohol. In the fields and along the country roads the stones and sticks that have been lying for some time on the ground should be carefully lifted and searched, both on the under surface and on the ground below. The stones and sticks should be turned back into the same places so that other spiders may find at once comfortable places to hide under. If they are dropped on new ground, it may be a year before they are fit to use again. Among trees and shrubs the best things are to be found by moving slowly about and watching for spiders, nests, and cobwebs without disturbing them. The webs can be best seen when moving toward the light. The greatest number of spiders can usually be found along paths and the edges of woods, and paths through the woods are the best places for many ground spiders. Spiders should be looked for in the same way in grass, by creeping along on the ground or by sitting down and watching until something walks into view; or the grass and weeds may be swept with a cotton bag, fastened on a hoop like a dip net, with a short handle, and the spiders picked out with a dry bottle from among the leaves and insects that will be gathered with them. Bushes may be swept in the same way, or may be shaken over an open umbrella, or a piece of cloth or paper. In winter, when spiders are torpid, great numbers can be found by sifting the dead leaves that have been lying for some years in the woods. A common coal sieve is fine enough to hold the leaves while the spiders and sticks and dirt pass through, and may be picked over on a cloth or carried home in a bag and examined in the house. The sifting should be repeated several times, as many of the spiders hold to threads among the leaves and become loosened only after much shaking. In the following pages a general description is given of each family, followed by descriptions of the species belonging to it, with a figure of each species placed as near as possible to the description. In some cases, where the genera are large and well defined, separate descriptions are given of each genus, but where the genus is not easy to distinguish or represented by only a few species, there is no separate generic description, and the species are placed next to those of other genera to which they are most closely related. If the names of spiders are known, they can readily be found by the index at the end of the book. If information is sought about an unknown spider, the illustrations through the book furnish the most convenient index, as the general form and proportions of spiders and the arrangement of their eyes usually show to what family they belong. The ground spiders and those without cobwebs are described first, and the sedentary species living in webs in the last half of the book. Readers unfamiliar with the subject are advised to read first the descriptions of the families and compare with them the spiders that they find in their own neighborhoods. The figures are in most cases enlarged for the sake of distinctness, and spiders of much smaller size must be looked for. THE COMMON SPIDERS THE DRASSIDÆ The Drassidæ, like the Lycosidæ (p. 67), are ground spiders, though some genera, like Anyphæna (p. 12) and Clubiona (p. 15), are equally common in summer on bushes. They make nests in the form of a bag or flattened tube, but no cobwebs for catching insects, and are commonly found running about among dead leaves and short grass and sometimes even on bare ground and sand. In form they are usually two or three times as long as they are wide, like the Lycosidæ (p. 67), but more often flattened on the back. The legs differ but little in length, and the first and second pairs are directed forward, the third and fourth backward. Their hairs and spines are short, giving them a smooth, velvet-like appearance. The feet have two claws, with a brush of flattened hairs under them, like the Thomisidæ and Attidæ (p. 41), but unlike the Lycosidæ (p. 67), which have three claws. The mandibles are large and strong and are together as wide as the head. The eyes are all about the same size and arranged in two rows of about the same length and not far apart, but between different species there are slight differences in their arrangement. The colors are usually dull gray, brown, and black, with few markings or none. A few species are very brightly marked, as in Micaria (p. 9) and Pœilochroa (p. 4). There are three groups among the Drassidæ: 1. Prosthesima, Gnaphosa, Pœcilochroa, Pythonissa, and Drassus, which are generally dark in color and flattened [Pg xvii] [Pg xviii] [Pg 1] FIGS. 3, 4, 5. Gnaphosa conspersa.—4, female enlarged four times. 3, the eyes seen from in front. 5, the maxillæ, labium, and ends of the mandibles from below. FIGS. 6, 7, 8. Pythonissa imbecilla.—7, female enlarged four times. 6, the eyes seen from in front. 8, the maxillæ, labium, and ends of mandibles from below. FIGS. 9, 10, 11. Pœcilochroa variegata.—11, female enlarged four times. 9, eyes from in front. 10, maxillæ, labium, and ends of mandibles from below. FIG. 12. FIG. 13. Pœcilochroa bilineata.— Upper and under views of female without the legs, enlarged four times. above, with the cephalothorax narrow in front and the eyes covering about half the width of the head and differing in their relative positions among the different genera. The labium is long and the maxillæ slightly widened at the end, or with the outer corners rounded off and sometimes a crease or depression in the middle. The joints of the first legs are sometimes thickened in the middle. The lower spinnerets are longer than the others and flat on the end. 2. Micaria, Geotrecha, Phrurolithus, Agrœca, and Anyphæna, in which the body is less flattened, the legs longer, and the movements quicker. The colors are lighter and more varied. The labium is short and the maxillæ with straight sides. 3. Clubiona, Chiracanthium, and Trachelas, in which the colors are plain and light, the eyes spread over more than half the front of the head and close to its front edge. The labium is as long as it is in Drassus, but contracted at the base. The maxillæ are narrow in the middle and flat and wide at the ends. Gnaphosa conspersa.—Half an inch long and rusty black in color. In alcohol the legs and cephalothorax are dark reddish brown and the abdomen gray. The whole body is covered with fine black hairs. The cephalothorax and abdomen are about the same size and a little flattened. The legs are stout and all nearly the same length. The upper row of eyes is nearly straight and the lateral eyes much farther from the middle pair than these are from each other (fig. 3). The middle eyes are oval and oblique, diverging toward the front. The maxillæ are large, and rounded on the outer corners. The mandibles are large and strong, with a wide, flat, serrated tooth (fig. 5) under the claw. The cocoon is white and flat, with a diameter as great as the length of the spider. The female, as far as I have observed, makes no nest, but partly lines with silk a shallow hole, in which she nurses her cocoon. It lives under stones and leaves as far north as the White Mountains and west to the Rocky Mountains in British Columbia, and on the Pacific coast in Oregon. A smaller and similar species, Gnaphosa brumalis, lives on the top of Mount Washington and as far north as Labrador. Pythonissa imbecilla.—About quarter of an inch long, bright orange brown on the cephalothorax and legs and blue black on the abdomen, with a few white hairs around the muscular spots. The legs are covered with fine long hairs a little darker in color than the skin. The cephalothorax is wide behind and more narrowed in front than in Gnaphosa. The eyes (fig. 6) are close together, and the lateral eyes of both rows are larger than the middle pairs and a little farther back on the head. The maxillæ (fig. 8) are short and wide, and bent toward each other so that they nearly meet in front of the labium. The front edges are nearly straight and the outer corners only slightly rounded. The sternum is wide and almost circular. The tarsus of the female palpi tapers from the base to the tip. Pœcilochroa variegata.—This is one of the most brightly colored of the family. The cephalothorax is bright orange, a little darker toward the eyes. The abdomen is black, with three transverse white stripes and a T-shaped white mark between the first and second stripes. On the front of the abdomen the white stripes are sometimes tinged with orange. The femora of the first and second legs are black. The distal end of the femur and both ends of the tibia of the fourth legs are black. Other parts of the legs are orange-colored. The female is quarter of an inch long. The cephalothorax is narrower than in Prosthesima atra and Gnaphosa conspersa, and the sternum longer and narrower. The maxillæ (fig. 10) are long and widened at the outer corners. The two rows of eyes (fig. 9) are almost straight, the upper one longer than the lower. Pœcilochroa bilineata.—A little smaller than P. variegata, but with the abdomen longer. Cephalothorax and abdomen both white at the sides and in the middle, with two black stripes from the eyes nearly to the spinnerets. The abdomen is covered with long hairs, black in the stripes and silvery white in the light portions. The legs are gray, with white hairs. The under side is light gray, with two black stripes at the sides of the abdomen that do not quite reach the spinnerets. The spinnerets are unusually long. The eyes are arranged as in variegata, the middle eyes being even more distinctly farther apart than they are from the lateral eyes. Prosthesima atra.—Black, and less than a third of an inch long. It may be mistaken for a small Gnaphosa conspersa, but, besides the small size, the abdomen is usually longer in proportion and the head is narrower than in Gnaphosa. The color is usually a deeper black and less likely to be gray in the young and rusty in the old, but the feet and under side of the abdomen are sometimes yellowish in the young. The eyes (fig. 14) are closer together and the two rows more nearly of the same length. In alcohol the cephalothorax and legs are blacker than in Gnaphosa and less brown. The maxillæ (fig. [Pg 2] [Pg 3] [Pg 4] [Pg 5] FIGS. 14, 15, 16. Prosthesima atra.— 16, female enlarged four times. 14, eyes seen from in front. 15, maxillæ, labium, and ends of mandibles from below. FIG. 17. FIG. 18. Prosthesima ecclesiastica. —Upper and under views of female enlarged four times. FIG. 19. Drassus saccatus. —Female enlarged three times. For eyes and mouth parts see figs. 1 and 2 in Introduction. FIGS. 20, 21, 22. Geotrecha crocata. —22, female enlarged four times. 20, eyes seen from in front. 21, maxillæ, labium, and ends of mandibles from below. FIG. 23. FIG. 24. Geotrecha 15) are a little longer and less rounded at the outer corners than in Gnaphosa or Pythonissa. The mandibles (fig. 15) are without the large teeth under the claw that Gnaphosa and Pythonissa have, and they are turned forward more than in those genera. It lives on the ground and under stones. The cocoon is white or pink, attached by the under surface, with the upper side convex and thickened in the middle, sometimes with a little dirt attached to it. Prosthesima ecclesiastica.—Black, with white markings along the middle of the back. One-third of an inch long, a little larger than P. atra and smaller than Gnaphosa conspersa. The cephalothorax is proportionally longer and narrower and the sternum narrower and less round than in P. atra (fig. 18). The cephalothorax is dull black at the sides, with a whitish stripe in the middle. The legs are also dull black and, like the cephalothorax, turn brown in alcohol. The abdomen is black, with a bright white stripe in the middle that extends from the front end about two- thirds its length; and at the hinder end, just over the spinnerets, is another white mark (fig. 17). The under side of the abdomen is dark at the sides and light in the middle. The eyes and maxillæ are as in P. atra, the maxillæ a little less rounded at the ends. Drassus saccatus.—Four-fifths of an inch long, and pale, without markings. The head is shorter and wider than in Gnaphosa conspersa and Prosthesima atra, and the eyes cover a larger part of the head. Both rows of eyes (figs. 2, 19) are curved, with the middle highest. The middle upper pair are oval and turned apart toward the front. The lateral eyes are twice their diameter from the middle pair. The maxillæ (fig. 1) are widened at the ends on both sides. The labium is as wide as it is long, narrowed toward the end but truncated at the tip. The color is light gray, with short fine hairs all over the body. The front of the head, the feet, and the mandibles and maxillæ are darker and browner. The abdomen is marked only with the usual four muscular spots and sometimes a few transverse dark markings toward the hinder end. The legs are long and tapering in both sexes. The male is smaller and more slender than the female, and the male palpi are long, with the end very little enlarged. They live under stones, and make a large transparent bag of silk in which the female makes her cocoon of eggs, and stays with it until the young come out. Early in the summer a male and female often live together in the nest, even before the female is mature. Geotrecha crocata.—Black, with the ends of the legs light yellow and a bright red spot on the end of the abdomen. It is about a third of an inch long. The legs are slender and the body is not at all flattened. The cephalothorax is two-thirds as wide as long, oval behind and narrowed in front of the legs, where the sides of the head are nearly parallel. The abdomen is oval and nearly twice as long as wide. The spinnerets are so far under the body that they show but little from above. At the front end of the abdomen is a spot larger below than above, where the skin is thicker and harder and browner in color than the rest. The cephalothorax is dark brown or black, as are also the femora of all the legs and of the palpi. The ends of the third and fourth legs are a lighter brown and the ends of the first and second legs and palpi light yellow. The abdomen is deep black except a bright red spot at the hinder end, which varies in size, is sometimes broken into several spots, or is sometimes wanting altogether. The eyes (fig. 20) are near together, the upper row curved down at the ends. The maxillæ are straight, with the sides nearly parallel, and the labium is shorter than wide. The males are usually smaller than the females and have the red spot larger. These spiders live among stones in dry open places. They are easily alarmed and move very rapidly. The flat, parchment-like cocoons found on stones are probably made by this species. Geotrecha bivittata.—The same size as G. crocata but much lighter colored, and with two white stripes across the abdomen (fig. 23). The cephalothorax is a little narrower behind than it is in crocata. Its color varies from orange to dark brown. The femora of all the legs are striped lengthwise with brown and yellow. The hind legs are brown, with a little yellow on the upper side of the patella and tibia. The other legs are yellow, sometimes with brown stripes on the under side. The white marks on the abdomen extend underneath halfway to the middle line. The sternum and under side are light brown. It lives under leaves at all seasons. [Pg 6] [Pg 7] [Pg 8] bivittata.—Upper and under views of female enlarged four times. FIGS. 25, 26, 27, 28. Micaria longipes.—28, Male enlarged four times. 25, eyes seen from in front. 26, maxillæ, labium, and ends of mandibles from below. 27, Southern variety, Micaria aurata. Colored orange, with black and white markings. FIGS. 29, 30, 31, 32. Phrurolithus alarius.—31, female in a natural position, with legs drawn up over the back, enlarged eight times. 29, one of the front legs to show spines. 30, eyes from in front. 32, maxillæ, labium, and ends of mandibles. FIGS. 33, 34, 35, 36. Agrœca pratensis.—33, eyes from in front. 34, maxillæ, labium, and ends of mandibles. 35, Micaria longipes or aurata.—A quarter of an inch long or less, and resembling an ant both in size and color (fig. 28). The cephalothorax is twice as long as wide, and only a little widened in the middle. It is highest in the middle, curving downward at both ends. The front row of eyes (fig. 25) is nearly straight and the upper row curved, with the middle eyes highest and the eyes all farther apart than in the lower row. The abdomen is one-half longer than the cephalothorax and about as wide, blunt at both ends and drawn in a little at the sides and above at a point a third of its length from the front. The legs are long and slender, the fourth pair longest. The colors are light yellow brown, with gray hairs and scales which on the abdomen have green and red metallic reflections. The legs are darker from before backward, the front pair all light yellow except the femur, and the third and fourth pairs with longitudinal brown stripes that nearly cover the tarsal joints. The abdomen has a pair of transverse white stripes near the constricted part and another pair less distinct at the front end. The under side is as dark as the upper. The white markings extend underneath halfway to the middle line. The maxillæ are nearly straight on the outer edge and a little widened toward each other at the ends. The labium is narrowed at the end and a little longer than wide (fig. 26). There is an orange-colored Micaria from Long Island, N.Y., and farther south (probably what is described by Hentz under the name Herpyllus auratus), that seems to belong to this species (fig. 27). Its size and markings are the same, and the epigynum is like that of longipes. The cephalothorax, abdomen, and femora of all the legs are bright orange color, with brilliant yellow and green reflections. The spinnerets are black, and there are five or six transverse black marks on the hinder half of the abdomen and some irregular black spots around the white bands. Phrurolithus alarius.—A small and very active spider marked with gray and white and having on the abdomen iridescent green scales (fig. 31). The cephalothorax is nearly as wide behind as it is long. The head is about half as wide as the thorax. The eyes (fig. 30) are large for so small a spider, and cover more than half the width of the head. The middle eyes of the upper row are oval and turned obliquely, diverging toward the front. The labium is short and the maxillæ straight, as in Agrœca and Anyphæna, but wider at the base (fig. 32). The legs are long and slender, except the tibia and metatarsus of the first and second pairs, which are twice as thick as the same joints of the other legs and have on the under side two rows of strong spines (fig. 29). The cephalothorax is light yellowish, with a black line on the edge each side, and two light gray stripes. The abdomen is gray, with transverse white markings that vary greatly in size and shape in different individuals. The abdomen is covered with scales that change from grayish green to pink with the motions of the spider. The legs are pale, except the patella and tibia of the first pair, which are black or dark gray, with the tip of the tibia white. The tibia and patella of the second pair are marked with lighter gray in the same way. It lives among stones in open ground, and runs short distances with great swiftness. When still it lies close to a stone, with the tibiæ drawn up over the back. Agrœca pratensis.—A little light-colored spider, resembling the next species, Anyphæna incerta. It is about a fifth of an inch long. The cephalothorax is wide behind and low in front and highest near the dorsal groove. The head is contracted in front of the legs more than it is in incerta. The front row of eyes is nearly straight, the middle pair only a little the higher (fig. 33). The upper row is longer and more curved, with all the eyes about the same distance apart, the middle pair not so much separated as in incerta. The abdomen is widest behind, but not as wide as in incerta. The spinnerets are two-jointed, as in Anyphæna. The legs are long, the fourth pair longest, and are a little thicker than those of incerta. The coxæ of the hind legs almost touch, and the sternum is short and nearly round (fig. 36). The labium is short and the maxillæ straight, as in Anyphæna. The cephalothorax, legs, and mouth parts are light brownish yellow. The cephalothorax has a fine dark line on each side and two broken longitudinal stripes made up of gray marks radiating from the dorsal groove. The abdomen has two rows of gray oblique markings on a light ground. The general appearance is like a small Lycosa. It lives among leaves and short grass. There is little difference between male and female. [Pg 9] [Pg 10] [Pg 11] back of female enlarged four times. 36, under side of female as far back as the epigynum. FIGS. 37, 38, 39, 40, 41. Anyphæna incerta.—37, palpus of male. 38, under side of female as far forward as end of sternum. 39, eyes from in front. 40, female enlarged four times. 41, maxillæ, labium, and ends of mandibles. FIGS. 42, 43. Anyphæna calcarata.—42, under side of cephalothorax of female. 43, palpus of male. FIGS. 44, 45. Anyphæna rubra.—44, female without the legs, enlarged four times. 45, under side of abdomen, showing position of air-tubes. Anyphæna incerta.—About a fifth of an inch long, light yellow, with gray markings. The cephalothorax is three-quarters as wide as long, rounded at the sides and highest in the middle. The front of the head is very low, so that the eyes nearly touch the mandibles. The front row of eyes is nearly straight. The upper row is longer and more curved, with the middle eyes highest and farthest apart (fig. 39). The abdomen is large in the female, widest behind the middle, and a little pointed behind. The labium is not longer than wide, and the maxillæ are straight, with the sides parallel. The sternum is oval, not so short and wide as in pratensis. The opening of the air-tubes is halfway between the epigynum and spinnerets (fig. 38), instead of just in front of the spinnerets, as it is in most spiders. The spinnerets are two-jointed. The legs are slender and tapering, the fourth longest in females and the first in males. The cephalothorax has two longitudinal broken gray bands. The abdomen has a double row of spots in the middle and oblique rows of smaller spots each side. The oblique lines of spots extend under the abdomen halfway to the middle. Anyphæna calcarata.—The same size and color as A. incerta, with longer legs. The markings are the same in both species. The plainest difference between the females is in the epigynum, the hard and dark parts of which are larger and longer in incerta. Another slight difference is in the shape of the sternum, which in calcarata extends farther between the hind legs (fig. 42). In incerta it is more pointed at the hinder end and shorter (fig. 38). The difference between the length of the legs in the two species, which is slight in the females, is greater in the males, the legs of calcarata being the longer. The palpi of the males differ considerably. In incerta (fig.37) the tibia of the palpus has a large process on the outer side close to the tarsus and extending along its edge a third of its length. In calcarata (fig. 43) the corresponding process is small and does not lap over the tarsus. The coxæ of the third and fourth legs of the male calcarata have little processes on the under side (fig. 42), one on the fourth and two on the third. These do not occur in incerta. It lives on plants like saltabunda (p. 14). Anyphæna rubra.—Larger than the other species, with the legs shorter. The female is about a third of an inch long, with the abdomen longer and narrower than in incerta or saltabunda. The opening of the air-tubes (fig. 45) is farther forward than usual, twice as far from the spinnerets as from the epigynum. The legs are comparatively short, the longest, the fourth, being about as long as the body. The maxillæ are a little widened at the end. The sternum is widest at the second legs and narrows to a point behind. The head is a little wider than usual, and the whole appearance more like Clubiona than the other species. The color is the usual pale yellow, a little brownish on the head and legs, and with two longitudinal stripes on the cephalothorax. The abdomen is nearly white, with two stripes made up of gray spots, and scattered spots at the sides. The spots turn red in alcohol. FIGS. 46, 47. Anyphæna saltabunda.—46, female enlarged six times. 47, palpus of male. Anyphæna saltabunda.—A pale short spider, with long and slender legs (fig. 46). The body is an eighth to a sixth of an inch long. The abdomen is oval, two-thirds as wide as long, and nearly as high as it is wide. The cephalothorax is three-fourths as wide as long, widest across the dorsal groove and narrowing gradually to half as wide in front. The [Pg 12] [Pg 13] [Pg 14] FIG. 48. Female Clubiona crassipalpis, enlarged four times. FIGS. 49, 50, 51, 52. Clubiona crassipalpis.—49, head and mandibles of male from the left side. 50, head and mandibles of male from in front. 51, palpus of male. 52, maxillæ, labium, and ends of mandibles. eyes of the upper row are twice as large as those of the front row. The first legs are longest in both sexes, measuring in the female over twice the length of the body and in the males three times. The spines are very long on the legs and palpi but only a little darker in color. The general color is pale yellow or white, with two broken gray stripes on the cephalothorax and two middle and several lateral rows of light gray spots on the abdomen. The spinnerets are slender and two-jointed. The opening of the air-tubes is halfway between the spinnerets and the epigynum. The palpi of the male (fig. 47) are long and slender, and the tibia is slightly curved and has a large thin process on the outer side. THE GENUS CLUBIONA These spiders are all pale and most of them without markings. The eyes are close to the front edge of the head and cover more than half its width (figs. 50, 54, 56). The upper row is longer and the eyes larger and the middle pair farthest apart. The distance between this pair varies according to the species. In crassipalpis and canadensis it is little more than that between the middle and lateral eyes, while in rubra it is nearly twice as great. The mandibles of the females are swelled at the base in front, and this swelling is greatest in canadensis (fig. 55). The mandibles of the males are longer and are shaped in a variety of ways according to the species. The shape of the epigynum is indistinct and variable, and females of different species are difficult to distinguish. The females of ornata and excepta are known by their markings and those of rubra by their size and resemblance to the male. The females of crassipalpis and tibialis are doubtful. The palpal organs and male palpi are of great variety and distinguish the males of all species without much difficulty. The Clubionas live in flat tubes of silk on leaves of low plants in summer and under bark and stones at all seasons. Clubiona crassipalpis.—A quarter of an inch long and pale, without markings. The head is sometimes a little darker than the rest of the body, and the mandibles and ends of the male palpi are always darker. The eyes of the upper row are almost equidistant, the middle pair only a little farther apart than they are from the lateral eyes. The mandibles of the male (figs. 49, 50) are elongated as usual, narrowed toward the end, and thickened in front just above the middle. On the outer side in front is a sharp ridge that extends from the base of the claw halfway up the mandible. The inner edges of the mandibles are thin and inclined backward toward the mouth, but there is no line or ridge between the thick and thin portions as in some other species. The palpi of the male (fig. 51) have the patella and tibia both short. The tibia is widened on the outer side and laps over the tarsus, extending in a blunt hook for half its length. Clubiona tibialis.—Quarter of an inch long, the same size and color as crassipalpis, with no markings and no dark color except on the mandibles and male palpi. The middle eyes are a litt...