$Phidippus tripunctatus.$--Black, with three bright white spots on the back of the abdomen (fig. 136). Large females are half an inch long and the males a little smaller. Though the general color is black, it is modified, especially in fresh specimens, by white hairs on parts of the body. The joints of the legs are grayish in the middle and black toward the ends. There are white hairs on the front of the head and upper side of the palpi and a white band around the front of the abdomen, plainest in the males. The three large white spots on the abdomen correspond to the second and third pairs in _mystaceus_ (fig. 135) and _multiformis_ (fig. 133), and the other pairs, though generally present, are small and inconspicuous. On the under side of the abdomen are usually two gray stripes. This is a common spider all over the country. It lives under stones and sticks and passes the winter half grown in a thick silk bag. [Illustration: FIG. 137. Plexippus puerperus.--Female enlarged six times.] [Illustration: FIGS. 138, 139. Plexippus puerperus.--138, male enlarged six times. 139, front of head of male.] $Plexippus puerperus.$--Very variable in size, from a third to half an inch in length. The females (fig. 137) are pale, light yellow, or almost white, with a few black spots, while the males (fig. 138) have the cephalothorax and legs brown, sometimes almost black. In both sexes the mandibles are large and the cephalothorax high and flat on the top as far back as the hinder eyes. The front middle eyes nearly touch each other. The lateral eyes are half their diameter higher than the front ones. The middle eyes are nearer the lateral than the dorsal. In the males the front eyes are nearly their diameter above the mandibles, and below them is a white band and a line of white hairs from the middle of the head down to the base of the first legs. The legs are rather slender in both sexes and long in the males. The fourth pair are longest in females, and in males the first and fourth are the same length. The markings of the abdomen are much alike in both sexes, with two light stripes, more definite in the males, bordered by a few small black spots irregularly arranged. The stem of the abdomen is long, and the abdomen and thorax appear farther apart than in many species. In the females the cephalothorax is pale, with a few gray spots from the middle toward the sides. In the males the legs are dark brown except the inner half of the femur of the third and fourth, which is light like the abdomen. The male cephalothorax is dark and has a square white spot between the eyes, two white lines pointing up from the third and fourth legs each side, and two short white lines under the dorsal eyes. The under side of the thorax and legs is dark or light like the upper side. The underside of the abdomen is usually darker in the middle and sometimes has a few black spots each side. This is a common spider in the southern states and has been found as far south as Brazil.