$Micaria longipes$ 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. [Illustration: 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.]