180 THE SOLITARY WASPS. 



garis, and juniperi, wliicli are very common at that time, but 

 their depredations are not confined to these species, as represen- 

 tatives of several families are often found in the same cell. 

 Hentz, the well-known arachnologist, said that he made some of 

 his rarest finds in mud-daubers' nests. Sex plays no important 

 part in determining the choice since when the males are abund- 

 ant they are commonly seized. In September, when many of 

 them mature, the proportion of the males to the females in- 

 creases. Dr. McCook, in his work on American spiders, says:* 

 "It is, however, true that in the gatherings of any individual 

 wasp there is apt to be a preponderance of a single species of 

 spider. Thus it would seem that a wasp starting out with 

 Epeira striw, for example, is apt to devote herself chiefly to 

 collecting that particular species." But after all the prefer- 

 ence, if any exists, is but little developed and propinquity is the 

 important factor in determining what arachnid is taken. 



An extract from our notes will give an idea of the contents 

 of these cells. 



Nest taken July 17 contained 9 Theridion tepadariorum. 



Nest taken July 17 contained 16 E. strix, 1 Tliomisid. 



Nest taken July 17 contained 10 young A. riparia, 4 Steadota 

 marmorata, 1 E. insularis, 1 unknown. 



Nest taken July 21 contained 5 E. insularis, 3 Phidippus rufus (1 

 male and 2 females, all mature), 1 A. riparia. 



Nest taken July 22 contained 9 Thoniisus ferox. 



Nest taken July 22 contained 9 A. riparia, 5 Steadota marmorata. 



Nest taken July 22 contained 15 E. lahyrintliea, 1 DendrypJiantes 

 militaris males, adult. 



Nest taken July 23 contained 12 Xysticus sp.? 



Nest taken July 23 contained 7 Phidippus 3-punctatus, 1 Xysticus 

 sp.? 



Nest taken August 18 contained 9 Orbweavers, {E. insularis and 

 juniperi). 



Nest taken August 18 contained 15 A. riparia. 



Nest taken September 14 contained 1 Misumena oblonga, 2 E. 

 vulgaris (1 male), 2 E. juniperi (1 male), 4 M. asperata, 4 E. strix, 1 E. 

 Z-punctatus. 



*American Spiders and their Spinning Work, Vol. :II, p. 386. 



