TRAP-DOOn SPIDERS. 195 



At Mentone two distinct spiders construct nests of 

 the cork type, one of these being a Nemesia and the 

 other a Cteniza. They are as unlike each other as 

 they well can be, and it seems remarkably strange 

 that their nest-building instinct should be so similar. 

 The nest of the Cteniza is indeed shallower than that 

 of the Nemesia, and a practised eye can usually trace 

 a difference between the slightly less angular lower 

 surface and more semicircular outline of tlie door of 

 the former, and the more abruptly bevelled and more 

 circular door of the latter. 



These spiders and their nests have been already 

 described and figured in Atits and Spiders under the 

 names of Ct.fodiens di,nA Nemesia ccementaria. Recent 

 discoveries have however shown that these spiders 

 possess distinctive characters of their own, and, though 

 closely allied to the species indicated, should be sepa- 

 rated from them. 



Last spring when pulling down an old terrace-wall 

 (by permission) I had the good fortune to discover 

 the very remarkable male Cteniza drawn at fig. A, 

 PI. XX., p. 25-1. I found no trace of a nest or web of 

 any kind, and the spider was merely hiding between 

 the stones. 



There appears to be scarcely any doubt that this is 

 the male of the female Mentonese Cteniza which has, 

 up to this time, been called Ct.fodiens. A comparison 

 with typical specimens of the true Ct. fodiens from 

 Corsica, has however shown that the two are cer- 

 tainly distinct, and Mr. Pickard-Cambridge* now 



Mr. Pickard-Cambriclgc has once more kindly undertaken the task of 



