SCHEFFER : COCOONING HABITS OF SPIDERS. 113 



Type: Xysticusmodestus. 



This is a small and not very common species, of sombre hues. 

 The female attaches her plano-convex cocoon lightly to the un- 

 der side of a stone and stays by it to afford it what material 

 protection she can. It is about a quarter of an inch in diameter 

 and consists of two valves, one of which is flat and attached to 

 the stone ; the other convex, forming a cap to the first piece. A 

 narrow border of the former projects beyond the latter. The 

 material of the envelope is thin but firm, and paper-like. It is 

 white in color. The eggs, about twenty-five in number, are 

 not agglutinate. In several instances that came under my ob- 

 servation in June the mother spider was found clasping a co- 

 coon which contained newly hatched young. 



Family ULOBORID^. 



We have three genera, including five species, of this family in 

 temperate North America. There are two types of cocoons — 

 the oval, plano-convex cocoon of Hyptiotes, and the elongate-de- 

 pressed-cylindrical form of the genus Uloborus. The former is 

 attached by the flat face to the side of a twig ; the latter is placed , 

 with others of its kind, along one of the rays of the web, like a 

 bead on a string. It is pointed at both ends, and has numerous 

 little projecting tufts which serve for attachment to the threads 

 that hold it in place. In all cases the cocoons are of paper-like 

 tissue. Hentz, speaking of the female of U. americanns guard- 

 ing her cocoon, says that nothing will induce her to leave it, 

 and that if it be torn from its place she will proceed to fasten it 

 down again. 



Type: Hyptiotes cavatus. 



This is the Triangle spider, whose interesting snare and pe- 

 culiar method of manipulating the same were first described by 

 Prof. B. G. Wilder. Nothing was known of its cocooning hab- 

 its, however, until the series of observations recorded in this 

 paper was begun. Two female spiders, imprisoned in glass 

 tubes the first week in September, furnished the key to the situ- 

 ation by spinning a cocoon each on the cork stopper. After 

 that, by careful search, any number could be found in the field, 

 though nearly all noticed for a week or so were old cocoons of 

 the previous season. They are usually located on the dead 



