SCHEFFER : COCOONING HABITS OF SPIDERS. 99 



There may be three or four such cocoons, but more commonly 

 only one. The females remain in the cell with the cocoon dur- 

 ing the period of incubation, and until the young are ready to 

 leave the parental nest. In many species they even seal up the 

 cell from the inside, that no marauder may intrude. 



Type: Phidippus ferrugineus . 



This large black and rust-colored species I have found only 

 on the limestone hills of central Kansas. The female passes 

 the winter in an oval dwelling-sack of stiff, closely woven tissue, 

 arched on one side, the other flat, and attached to the under 

 surface of a loose stone. Small sticks and bits of leaves are 

 used to partly cover the sack, or at least to surround its base. 

 There is no opening for egress. In April the occupant spins 

 a cocoon of fleecy adhesive silk, attaching it to the walls of the 

 sack. It is depressed spherical or biconvex lens-shaped, pure 

 white, like the sack, and about three-eighths of an inch in greatest 

 diameter. Immediately investing the eggs is an inner envelope 

 of somewhat firmer silk, about as thick and smooth as ordinary 

 tissue paper. The eggs are yellow, not agglutinate, and num- 

 ber about 140. After they hatch the young remain sealed up 

 in the sack with the mother for at least two or three weeks. 



Type : Phidippus opifex. 



This species, from California, makes its cocoon nest in some 

 shrub, as sage. It is an egg-shaped mass of white spinning 

 work, about three inches long by two and one-half broad — 

 sometimes less. In August or September the mother spins in 

 this nest from two to four white, lenticular cocoons for her eggs. 

 They are attached to the walls, and shut off from the part of 

 the nest the mother occupies by a thin sheet of web. Each 

 consists of a shallow concave disk on which the eggs are placed 

 and a convex cover for the same fastened down by a few loose 

 threads at the junction. The eggs are pinkish red in color. 

 The young are said to remain in the cottony nest until spring 

 (Davidson) . 



Family ATYPID.^. 



Four genera, including six species, of this family of burrow- 

 ing spiders are accredited to temperate North America — these 

 mainly on the authority of Simon or Hentz, Little has been 



S-Bull„ Vol. Ill, No. 2. 



