86 TRAP-DOOR SPIDERS. 



It will be seen tliat species belonging to the same 

 genus, and closely resembling one another, sometimes 

 build dissimilar nests ; wliile others, belonging to 

 different genera, and unlike in many important 

 respects, construct almost identical nests. 



This is the more strange, because, if we examine 

 the structure of the claws and palpi, they often seem 

 to be specially adapted to serve as carding instruments 

 and to play a very important part in the weaving of 

 the silk linings of the nest ; and yet nests of the same 

 type are occasionally produced by spiders in which these 

 appendages are quite unlike, and dissimilar nests where 

 the claws and palpi are to all appearance identical. 



Thus, for example, if the reader will examine the 

 drawings of part of the foremost right foot of Cteniza 

 fodieus, figs. A, 9 and 10, Plate VII., p. 88, with that of 

 Nemesia C(jem.enfaria,^^^s. A, 9 and 10, Plate VIII., p. 94, 

 both of which make nests of the cork type, he will see 

 that in the former the last joint of the tarsus is armed 

 along the inner side, with many moveable spines, and 

 that each of the two curved terminal claws has only 

 one very strong tooth near the base ; while the same 

 joint of the latter {N.ccementaria) has no spines, and the 

 claws have three minute comb-like teeth near the base. 



On the other hand, in the reverse case, where the 

 structure of the same joint is very similar, the nests 

 may be wholly unlike, as in Nemesia Eleanora, Plate 

 XII., p. 106, and N. ccBmentaria, Plate VIII., where the 

 nest of the former is of the double-door unbranched 

 type, and that of the latter of the single-door cork 

 type. ^ 



It is probable however that a fuller and closer 

 comparison of, and a more exact acquaintance with the 



