The Linyphiadæ consist of a great number of species of small spiders living, for the most part, in shady woods, among the lower branches of plants, under leaves, and in caves and cellars. They differ from the Therididæ generally in having the body more elongated, the legs stouter and with more spines, the mandibles larger and stronger and furnished with teeth around the claw, and the maxillæ straighter and not inclined inward toward the labium. There are two groups among them,--Linyphia and its allies, which are comparatively large and some of which live in the open woods, with large cobwebs, and Erigone and its allies, which are all very small spiders, living mostly in short grass, dead leaves, and moss. The latter usually have narrower bodies and stouter legs, resembling the Drassidæ. Their colors are generally plain and dull, and the females are difficult to distinguish from each other, while the males often have peculiar modifications of the head and proportionally very large and complicated palpi. The webs usually have a large flat sheet, supported by threads above and below, under which the spider lives. Some species have the sheet of web curved upward or downward. _Linyphia marginata_ forms a dome-shaped web four or five inches in diameter. THE GENUS LINYPHIA These spiders vary in size like the species of Theridium, from a quarter of an inch to a tenth of an inch long. In appearance they differ greatly from Theridium; the cephalothorax is longer and higher in front, the legs are long and slender, with distinct spines, and the abdomen is sometimes a little flattened on the back as in Steatoda, but oftener high in front and a little pointed toward the spinnerets. The sexes differ little in size, but often in color and markings. The palpal organs and the terminal joints of the palpi of the males are very large and complicated, and in the smaller species form the best means of distinguishing them. There are a great number of minute species of Microneta, Bathyphantes, and other allied genera, but only the larger and more common are here described. [Illustration: FIG. 318. Web of Linyphia marginata. Half the real size.] [Illustration: FIGS. 319, 320. Linyphia marginata.--319, female enlarged eight times, showing markings of the back. 320, side of abdomen.]