TRAP-DOOR SPIDERS. 193 



and Gr represent on a reduced scale five types of wafer 

 nest constructed by as many distinct spiders, and 

 where a gradation may readily be traced between the 

 simplest type at C and the most complicated at Gr; but 

 we shall speak more fully of tliis matter by-and-by. 



In these diagrams I have placed that representing 

 the nest of Atypits on the extreme left (A) ;^ next to 

 this stands that of a nest of the cork type (B), a 

 tj'pe which must be carefully distinguished from all 

 the rest. It must not be supposed that the solid 

 cork door (so called from its resemblance to a short 

 cork closing the neck of a bottle), is nothing more 

 than a thicker edition of the wafer door ; it is not so, 

 but, on the contrary, possesses a very characteristic 

 structure of its own, being composed of many layers 

 of silk, each furnished with a sloping rim of earth, 

 while the wafer door consists of but a single layer of 

 silk. 



I have represented at B 1 the 14 layers of silk 

 and earth which went to make a single cork door 

 examined by me. It will be seen that the outermost 

 of these layers is the largest, and the innermost the 

 smallest, and I have already {Ants and Spiders, p. 150j 

 shown reason for believing" that the latter constituted 



* These types may be briefly enumerated as follows : 



A, nest of Atijpus. 



B, cork nest, and B, 1, layers of silk and earth forming the door of the cork 

 ne St. 



C, single-door, unbranched wafer nest. 

 l->, single door, branched wafer nest. 



E, double-door, unbranched wafer nest, and E, 1, lower door of the same. 



F, the Hyeres double-door branched wafer nest, and F, 1, lower door of the 

 same. 



Or, double-door branched cavity wafer nest, as seen in the oldest and largest 

 specimens, and G, 1, the same in the younger specimens. G, 2, the lower door 

 of this nest, being of the same form in yoang and old nests. 



