THE GENESIS OF SNARES. 



343 



any apparent purpose of the spider, drop into a maze of interlacing single 

 threads, which would present in crude form the typical snare of such 

 genera as Theridium, Pholcus, Ero, Xeriene, and others of the 

 Retitelarige. That web is, in point of fact, just such a snare as 

 I have seen other spiders make, notably the Orbweavers, by such 

 purposeless moving back and forward as I have mentioned. 

 To be sure, the snares of Theridium and Pholcus, as we now see 

 them, have a little more finished character than that of the crude cobweb 



Therid- 

 ium 's 

 Parental 

 Snare. 



FIG. 334. The sheeted web of Linyphia costata. 



described, but the difference is not very great, and it therefore implies a 

 rigid persistence in habit throughout an immense period of time. 



We take another step in the development of web making, confining 

 ourselves still to the tribe of Lineweavers. I have already described, in 

 the chapter on Engineering Skill, the manner in which Theridium tends 



