112 KANSAS UNIVERSITY SCIENCE BULLETIN. 



Family THOMISID^. 



The Crab spiders make no web. They lurk in green foliage 

 or flowers during the summer, and in winter species that sur- 

 vive find shelter under the bark of dead trees or under stones 

 and leaves. The cocoons are usually lens-shaped and attached 

 by one side, though sometimes they are free or suspended, like 

 a hammock, in a shelter of leaves. There may be two valves 

 united at the border, which presents, in this case, a little circu- 

 lar fringe. In some cases the cocoon is attached by a few 

 threads within one or more leaves drawn together. Again it 

 can be found in the tops of dead grasses or in flower clusters. 

 Still other chosen sites among some species are the trunk of a 

 tree, the angle of forked twigs, or the arch of a stone. The 

 tissue of the cocoon is sometimes compact, sometimes of a flossy 

 nature and adhering to the touch. It is unlikely that any 

 species makes more than one cocoon in a season. The mother 

 spider is observed to quit her wandering habits and become 

 more sedentary when rearing her brood. In some cases she 

 watches over her eggs and progeny, but several of our common 

 species wander off as soon as the cocoon is finished. 



Type: Philodromus vulgaris. 



The cocoon is spun in the fork of a twig, or occasionally in a 

 slight depression on the trunk of a tree or the surface of a stone. 

 The outer covering consists of very stiff, tightly stretched, 

 milk-white silk, getting thinner toward the edges. This en- 

 closes the angle between the twig and the branch, curving 

 downwards a little on its upper border. Under this, and not 

 in contact with it, is another similarly stretched fold of less 

 compact silk covering fifteen to twenty reddish eggs. Under 

 the eggs, next to the bark of the twig, is a light carpet of filmy 

 silk. The eggs are not agglutinate, but are entangled some- 

 what by light threads. 



The cocooning season occupies the latter part of September 

 and most of October. The young hatch in a few weeks, but 

 remain in the shelter of the cocoon until spring. The mother 

 spider is never found about the cocoon unless she has not yet 

 given the finishing touches to it. 



