Agalena nævia.—This spider is known everywhere by its web, which it makes on grass, among stones and weeds, and in houses (figs.221, 222). It varies greatly in size and color. Large females may be three-quarters of an inch long, with legs measuring an inch and a quarter, while others may be full grown at half that size. In color some are pale yellow with gray markings, and others reddish brown with the markings almost black. Whatever the color, they are thickly covered with fine gray hairs. The cephalothorax has two longitudinal gray stripes and a black line along the edge on each side (fig. 223). The head is high and a little darker in front. Both rows of eyes are strongly curved, with the middle eyes highest, so that the middle eyes of the lower row and the lateral of the upper row form a nearly straight line (fig.224). The mandibles are stout, not much swelled in front, and covered with hair. The abdomen is gray or black at the sides and lighter brown in the middle, with two rows of white or light-colored spots. The upper spinnerets are more than twice as long as the others, and the terminal joint much longer than the basal. The legs are large and long, the fourth pair almost twice as long as the body. The legs are marked with dark rings at the ends of the joints and lighter rings in the middle of femur and tibia. On the under side the coxæ are light colored and the sternum dark, and there is a broad dark middle band on the abdomen from the hinder legs to the spinnerets. The males are as large as the females, with longer legs and smaller abdomen. The male palpi have a very large black tube coiled one and a half turns under the tarsus (fig. 225). The web (fig. 222) is flat and shaped according to the surrounding objects to which it is fastened, with a tube at one side in which the spider hides. The eggs are laid in August and September in a flat cocoon, attached by one side in some sheltered place and covered with silk, often mixed with dirt. Most of the adult spiders die before winter, and females are often found dead on or near their cocoons. The young hatch in the winter and leave the cocoon early in the spring, and soon begin to build their webs among the short grass. The webs become more distinct when covered with dew, but, though too transparent to be seen at other times, they remain in the same places throughout the summer and are repaired and enlarged as the spider grows. If, however, the web should be destroyed, the spider is able in one day to make a new one as large as the old, but thin and transparent. The web contains many long threads crossing it from one side to the other and nearly parallel, and these are crossed in all directions by finer threads (fig. 226). The long threads are spun from the lower spinnerets, the upper pair being held up over the back, out of the way. The fine threads are spun from the upper spinnerets, which are swung from side to side as the spider moves along. There is nothing adhesive about the web. It serves merely as a clearing where insects may alight to rest and the spider may have a good chance to run after them. Where the web is made under plants or rocks a great number of threads are carried upward from it, which may help in stopping insects (fig. 227), as they do in the webs of Linyphia. (See p. 135.)

Tegenaria derhamii.—This is a common species in barns and cellars, and has probably been imported from Europe, where it is even more common. The head is high and wide, as in T. medicinalis. The mandibles are less swelled in front and the eyes are closer together than in that species, and cover more than half the width of the head (fig. 229). The cephalothorax is shorter and wider across the hinder half and the abdomen shorter than in medicinalis, and the legs are longer and more hairy. The colors are lighter and the hairs of the whole body longer. The female is two-fifths of an inch long. The cephalothorax is pale, with two gray stripes. The abdomen is marked with a series of gray spots, formed of a middle row more or less connected with two side rows; the front of the abdomen often pale, with the markings faint (fig. 228). The legs are long, the first and fourth pairs nearly twice the length of the body. They are marked with faint gray rings at the ends and two in the middle of each joint. The palpi are long and slender in both sexes, and those of the male have the patella and tibia of about the same length and each nearly twice as long as wide. There are no processes on the patella, but two small teeth on the tibia near its end. The tarsus is small and narrow, not as long as the patella and tibia.

The webs are made in all parts of cellars and unswept buildings, sometimes forming a shelf in the corner, not as large or as flat as those of A. nævia, but with a similar tube on the most sheltered side (fig. 230). The webs more often spread under beams and floors fastened up by threads at the sides and edges, and, as they gather dust, hang down by its weight and become torn and tangled. Old webs are repaired and extended until they become as thick as cloth with silk and dirt. The tube is generally smaller and less funnel shaped where it enters the web than that of Agalena. The web is not as flat as that of Agalena, curving usually down from the tube and up in front of it, often turning up abruptly at the edge. Sometimes it is fastened up in the middle of the front edge and curves downward each side (fig. 232).

Fig. 231 shows a web of the most common form in the corner of a cellar, with the spider standing at the mouth of the tube, and the remains of egg cocoons hung up at the left. This web was at least a year old, and the front edge had just been extended with clear and transparent silk, while the middle was black with coal dust.

Fig. 232 is another web in the same cellar, with the front edge fastened up to the boards above. It is drawn tightest in the middle and curves down on each side.

Tegenaria (Cælotes) medicinalis.—A large gray spider living in the woods, among rocks, in hollow trees, and under loose bark. It is half an inch long, with the legs of the female not much longer (fig. 233). The head is large and wide, and the eyes cover a little more than half its width. It is a little constricted in front of the legs and raised above the thorax as far back as the dorsal groove. The abdomen of the females is large and oval, widest across the hinder half. The spinnerets are small, but plainly two-jointed, and the upper pair longest. The general color is light yellow brown, covered with gray hairs, the cephalothorax browner, and the abdomen grayer, than the legs. The cephalothorax has two indistinct gray stripes. The abdomen is marked with a series of gray spots of irregular shape, smallest toward the front and larger and darker toward the end. The legs are faintly ringed with gray, more distinctly in the young.

The males are as large as the females, with smaller abdomen and longer legs. The palpi have the patella and tibia short, not much longer than wide (fig. 235). The patella has a short process on the outer side near the end. The tibia is of complicated shape, as shown in the figure. The tarsus is twice as long as the tibia and patella together, with a long narrow tip. The palpal organ is large and complicated, with a long fine tube that can be seen from above, where it curves around the base of the tarsus.

The epigynum varies in appearance according to the thickness and color of different parts. The two figures show common varieties (figs. 236, 237). This species and longitarsus are both easily mistaken for Amaurobius sylvestris and ferox, which are of the same size and color and live in the same situations. Amaurobius does not have the long upper spinnerets like Tegenaria, the eyes are lower on the front of the head, and there are larger light-colored markings on the front of the abdomen. The young of Tegenaria medicinalis are pale, with light gray markings, and the cephalothorax is marked with spots radiating from the dorsal groove (fig. 234). The web of this spider is not flat like that of Agalena, but curved in various shapes according to the place where it is built. If there is an open level place near the nest, the web spreads across it, but usually curves upward at the edges and is fastened to surrounding stones and weeds. Where the spider lives in the cracks of a wall or rock, the net spreads along the surface of the rock, held away from it a short distance by threads fastened to projecting points on the stone (figs. 239, 240). This species is sometimes mistaken for the longer legged and more hairy Tegenaria derhamii (fig. 228), that makes similar webs in barns and cellars.

Tegenaria (Cælotes) longitarsus.—Smaller than medicinalis; about two-fifths of an inch in length. The head is very wide, and the mandibles of the female more swelled in front than in medicinalis, and the eyes are smaller and cover less than half the width of the head (figs. 244, 245). The cephalothorax is darker colored in front and does not have the two longitudinal stripes seen in medicinalis (fig. 241). The legs are only faintly marked with gray in the middle of the joints. The abdomen is marked with gray, in a series of dark and light spots, as in other species, and of more regular shape than in medicinalis. The epigynum is light colored, with a middle bar covered with hair and slightly forked at the hinder end (fig. 242). The male differs in the usual way from the female and has the palpi shorter than medicinalis. The tarsus has a projection at the base that covers the tibia. The patella has a short process on the outer side that points directly forward (fig. 243).

Tegenaria (Cicurina) complicata.—A small spider, resembling the young of the larger species of Tegenaria, found usually under dead leaves in woods (fig. 246). It is a fifth to a quarter of an inch long, with the longest legs one and one-half times as long as the body. The spines of the third and fourth legs are long and stout, and there are long fine hairs on all the legs and the abdomen. The color is pale yellowish brown, lighter on the abdomen, which has faint gray markings. The sexes are much alike, and both vary in size. The palpi of the males are very large and conspicuous (figs. 248, 249). The patella is short and wide, and the tibia is narrower at the end and wide toward the base, where it has a short process on the outer side. On the under side of the tibia is a long thin appendage of irregular shape that is nearly as long as the tarsus. The tarsus itself is long and narrow, and the palpal organ large and complicated, with a long fine tube that extends from the base along the outer side and back to the hard appendages in the middle. The epigynum (fig. 247) has a small, transverse, oval opening at the hinder end, in front of which the coils of long tubes can be seen through the skin.

In New England Agalenidæ Pl. VII, fig. 2 is the epigynum of this species and not of Cælotes longitarsus.

Hahnia bimaculata.—The Hahnias resemble Tegenaria, but are much smaller and have the spinnerets extended in a line across the under side of the abdomen (fig. 251). Hahnia bimaculata is about one-eighth of an inch long, with the abdomen large and oval, widest behind, as it is in Cælotes (fig. 250). The cephalothorax is bright orange brown, and the legs and abdomen pale yellowish with gray markings. The legs are ringed with gray, the longer joints having two rings, and the abdomen has a pattern of light yellow and gray spots. The spinnerets are all long and in a nearly straight line, half as long as the width of the abdomen. The outer or upper pair are half as long as the abdomen, and the two joints are nearly of equal length. The tracheal opening is in the middle of the abdomen, nearer the epigynum than the spinnerets. The sternum is as wide as long, widest opposite the second legs. The maxillæ are straight in front and have a slight projection at the outer corners, where there are two or three stiff hairs. In some other species there is a longer process at these corners.

This spider is common in winter under stones and under leaves. In summer it makes webs close to the ground, among short and thin grass and moss.

Hahnia cinerea.—About a twelfth of an inch long; much smaller than bimaculata (fig. 251). The color is dark gray, the cephalothorax and legs brownish, and the legs a little lighter at the ends of the joints. The abdomen has a row of angular light spots in the middle. The spinnerets are in not quite as straight a line as in bimaculata, the outer pair being a little higher and farther behind the next. The tracheal opening is not as far forward as in bimaculata, being nearer the spinnerets than the epigynum. The male palpi have the appendages of patella and tibia longer than in bimaculata, and softer and more curved. They are found under stones and leaves.

THE THERIDIDÆ

The Therididæ are the builders of the loose and apparently irregular webs in the upper corners of rooms, in fences and among rocks, and between the leaves and branches of low trees and bushes. They are generally small, soft, and light-colored spiders, with the abdomen large and round and the legs slender and usually without spines. The eyes are all about the same size and in two rows across the front of the head, with the lateral eyes of the two rows near together and often touching each other. The mandibles are weak and without teeth at the end. The maxillæ are pointed at the end and turned inward toward each other. Most of the Therididæ live always in their webs, hanging by their feet, back downward. The webs have in some part a more closely woven place under which the spider stands, sometimes in the middle of the web, sometimes in a corner out of sight. Where the spider's usual standing place is without other shelter, it is often concealed by pieces of leaves or sand carried into the web by the spider, and sometimes made into a tent. The outer part of the web is usually loosely made in large meshes, but is sometimes in a distinct sheet spreading from the nest and held out by threads in all directions. The cocoons are round and soft and hang in the web, several being made in the same season by one spider.

Several of this family, like Spintharus and Euryopis, have the abdomen smaller and flatter than usual and the fourth legs longer, so that they are better fitted for walking. They are found on plants, and little is known about their webs.

THE GENUS THERIDIUM

The Theridiums are small soft-bodied spiders, making large and loose webs without any large flat sheet of silk, but only a slightly closer portion where the spider stands, or a nest or tent connected with the web. Theridium tepidariorum (fig. 258) and rupicola (fig. 261) live in houses or among rocks, making large loose webs, in which the spider often stands without any covering. They have the abdomen high in front and tapering a little toward the spinnerets. Theridium globosum (fig. 262) has the abdomen of the same shape. The other species are all small and have the abdomen round and brightly colored. They live in more open places on plants, where they make nests in which they are partly hidden, and carry their webs over the neighboring leaves and twigs (figs. 253, 254).

Theridium tepidariorum.—This is one of the most common house spiders, and is often found in its webs among rocks, but seldom on plants. The females (fig. 258) measure sometimes over a quarter of an inch in length, but may mature much smaller. The legs of the first pair are nearly three times the length of the body. The male (fig. 259) is shorter and has longer legs. The color varies from dirty white to almost black. The cephalothorax is yellow brown, and the legs light yellow, with brown or gray rings at the ends and the middle of the joints. In the males the legs are orange brown, darker at the ends of the joints. The abdomen is high in front and narrows toward the spinnerets. In dark and well-marked specimens the abdomen has, on the hinder part, six transverse black marks curved upward, thicker in the middle, and partly connected by black spots at the ends (fig. 260). These marks are most sharply defined on the hinder edge, where they are bordered by silver white. The upper mark often forms a conspicuous black and white spot in the center of the abdomen. In light individuals all the markings are smaller and less definite.

It makes a large web in the corners of rooms, under furniture, and in the angles of fences and between stones (fig. 255). It usually stands in the most sheltered part of the web, where a part of it is more closely woven than the rest, but not enough so to conceal the spider. It occasionally makes the web in an open place where there is no shelter above, and then it sometimes carries a piece of leaf into the web and hides under it, as is the usual habit with some allied species. The webs of the young are usually more regular in form than those of adults (figs. 256, 257). A male and female often occupy the same web for a long time. The eggs are laid in brownish pear-shaped cocoons, several of which are made in the same season by one spider and hang in the web. This species is found all over the world.

Theridium rupicola.—This resembles closely tepidariorum and is easily mistaken for the young of that species. It does not grow larger than an eighth of an inch long. The colors are like tepidariorum, usually dark gray with black spots, the back of the abdomen sometimes almost white. The legs are distinctly ringed with light and dark. In the middle of the abdomen is a pointed hump, the front part generally black and the hinder part white (fig. 261).

It lives under stones and among rocks, in webs like those of tepidariorum, often containing grains of sand which look as if placed there by the spider, as sand falling into such a web would go through without sticking to the threads.

Theridium globosum.—This is another species with a high abdomen like tepidariorum. It is about a twelfth of an inch long and almost as high (fig. 262). The abdomen is a little flattened behind and pointed toward the spinnerets. The hinder part is white, with a large black spot in the middle, below which is sometimes a smaller black spot. Sometimes there is a bright white line around the light area. The front upper part of the abdomen is yellowish gray, and the under part brown. The cephalothorax is orange brown, except a black spot between the eyes. The legs are orange brown.

Theridium differens.—Female about one-eighth of an inch long, and the male smaller. The abdomen is round, and the middle stripe often very brightly colored, with white or yellow at the edges and red in the middle (fig. 264). The rest of the abdomen is reddish brown, darkest next to the white edge of the stripe. There are no distinct marks on the under side. In males the stripe on the abdomen is obscure, and the whole abdomen dark reddish brown (fig. 265). Sometimes, especially in young spiders, the abdomen is entirely yellow, with indistinct brown markings. The cephalothorax is orange brown, often darker in the middle, but with no distinct stripe. The legs and palpi are yellow in females and orange brown in males, slightly darker at the ends of the joints. The epigynum has no openings in sight. They are on the inner side in the transverse fold across the abdomen. The palpal organ (fig. 266) has two appendages at the end, one hard and roughened and the other soft. The web is on low plants of all kinds, usually two or three feet from the ground (fig. 263). There is sometimes a small tent, often hardly deep enough to cover the spider, from which the web spreads two or three inches, according to the shape of the plant. The cocoons of eggs are white and nearly as large as the spider, and are attached in the nest.

Theridium murarium.—Length about one-eighth of an inch, with the abdomen nearly spherical. The general color is gray. The legs are pale, with dark bands at the end and middle of each joint. The cephalothorax is pale, with a dark line in the middle and one on each side, the middle line sometimes divided into two near the eyes (fig. 267). On the abdomen there is an undulated middle stripe, white at the edges and the front end, and reddish in the middle. On both sides of this stripe the abdomen is nearly black and becomes gradually lighter toward the sides. The sternum is pale, with a black edge and black stripe in the middle. The under side of the abdomen is gray, with a long black spot in the middle and a smaller one over the epigynum. There is little difference in size or color between the sexes. The epigynum (fig. 269) has two round holes, wide apart, near the thickened edge. The palpal organ (fig. 268) is shorter and simpler than it is in differens.

Theridium spirale.—This is a round-bodied spider of the same size as differens and murarium. The cephalothorax is orange brown above and below, with an indistinct dark stripe as wide in front as the eyes and narrowed behind. The abdomen has a middle stripe like differens, nearly as wide in front as it is in the middle (fig. 271). The rest of the abdomen is gray, darkest toward the stripe. The legs are pale, sometimes with faint gray rings at the ends and middle of each joint. The middle stripe of the abdomen is sometimes reddish as in murarium, but oftener gray, with a dark spot near the front end. The males (fig. 270) have the same color and markings as the female and are sometimes more distinctly marked. The male palpi (fig. 272) are very large, and the palpal organ has a long tube coiled on the under and outer side. The openings of the epigynum (fig. 273) are about their diameter apart.

Theridium frondeum.—White, light yellow, or greenish white, with black markings that are very variable (fig. 274). Usually the cephalothorax has two fine black lines running back from the eyes and uniting behind the dorsal groove, and black edges. The legs are usually darkened with brown at the ends of the joints. The abdomen is large and round, and has on the back a light undulated band bordered by brownish translucent spaces, with two black spots just over the spinnerets. Sometimes there are black spots in the translucent spaces, especially toward the hinder end, and these may be united into two long black stripes. In some individuals of either sex the black on the cephalothorax forms a wide band in the middle, almost covering the back, and a black stripe of similar width extends backwards on the abdomen for half its length. These black-striped individuals have all the other variations of color and markings. The males have all the colors and spots brighter and the legs longer than the females. The mandibles of the male are longer than those of the female and have at the base, in front, a low conical point.

This species is found from the White Mountains to Alabama. In New England it matures in July and is found on bushes all summer.

Theridium unimaculatum.—This little species differs in color and markings from all the others, and may almost always be distinguished by the white abdomen, with a black spot in the center of the back. The females are a twelfth of an inch long and the males smaller. The cephalothorax is orange yellow, with a black spot around the eyes, extending back in a point as far as the dorsal groove, and there is also a fine black line along the edges. The legs are orange, lighter in the female and darker in the male, with the first and second pairs in the male much stouter. The sternum is orange, with black edges. This spider makes a web, like the other small species, among small leaves and winters under dead leaves on the ground.

THE GENUS STEATODA

Steatoda has the legs shorter and stouter than Theridium. The abdomen is oval and often a little flattened on the back. It is smooth and shining, the hairs being fine and scattered so as to be hardly visible. The thorax is thick and hard, and in some species marked with hard projections and depressions. The head is generally narrow, and the front middle eyes are in several species larger than the others and farther forward and wider apart. In other species all the eyes are about the same size. The webs consist of a flat sheet supported and held down by threads.

Steatoda borealis.—This is a dark reddish-brown spider, quarter of an inch long, living among stones or in the corners of fences and window frames, generally well concealed by its web or nest. The cephalothorax is orange brown and covered with short stiff brown hairs. The head is one-third as wide as the thorax and a little higher, the eyes near together, with the front middle pair projecting forward beyond the mandibles (fig. 279). The legs are brown, with faint darker rings, and are thickly covered with hairs. The abdomen is dark chocolate brown, sometimes without any light marks on the upper side, but usually there is a light line running around the front half and another in the middle, extending back half the length of the abdomen and usually broken into several spots. The four depressed spots on the abdomen are distinctly marked. On the under side there is a light stripe on each side, meeting behind the spinnerets. The sexes are much alike in size and color, but the palpi of the male (fig. 278) are longer than the cephalothorax, and the terminal joint is very large and complicated. The web consists of a flat sheet, held out by threads in all directions, but is often so crowded into a corner that its structure is hard to understand (fig. 276).