100 KANSAS UNIVERSITY SCIENCE BULLETIN. 



recorded concerning their cocooning habits, and, as they are 

 found only in the South or on the Pacific coast, I have had no 

 opportunity to observe them. I present two somewhat conflict- 

 ing statements relative to the genus Atypus — all I could find on 

 this family. "At the bottom the burrow widens out a little in 

 the form of an oblong chamber, and it is at the entrance to this 

 chamber that the female suspends her cocoon, which has the 

 form of a little sack of white, closely woven material " ( Simon) . 

 "The female deposits her cocoon at the end of her burrow; 

 this is guarded from the dampness of the earth by being placed 

 on a cushion formed of silky flock and the fibers of plants" 

 ( Staveley) . 



Family AVICULARIID^. 



Considerable has been written about the interesting habits of 

 these Trap-door spiders of the West and Southwest, but most 

 of the writers seem to have neglected observations with which 

 this papej" is concerned. 



Wht/U tlie egg-laying season arrives, many species of this 

 family completely close up their burrows by sealing the trap- 

 door to the walls. The single cocoon containing the eggs is 

 then suspended near the bottom of the tube or in one of the 

 chambers, if it has diverticula. The cocoon is a fairly close- 

 woven sack in some species, but in others, particularly of the 

 genera BotJiriocyrtum and Cteniza, the eggs are held in place 

 merely by a few threads. Members of the subfamily Avicu- 

 lariimie, like species of the Pholcidae and Pisauridse, carry their 

 large, rounded, flabby cocoons about in their chelicera? until 

 the time of hatching. The young, as a rule, remain for some 

 time in the burrow with the mother, but at an early age are 

 said to build perfect trap-door nests for themselves. 



Family CLUBIONID^. 



This is a large family, including a number of groups that 

 differ considerably from one another in cocooning habits. With 

 all the diversity, however, the general methods of procedure 

 will usually follow one of three lines. The most common prac- 

 tice is to enclose the more or less lens-shaped cocoon in an outer 

 dwelling-sack, or special incubation cell, like most of the Sal- 

 ticidse. In a few cases this outer sack is a mere veil of silk, 

 but more often it has thick walls of double or triple tissue, and 



