TRAP- DOOR SPIDERS. 85 



and described by Prof. Westwood,* whicli seems in- 

 termediate between the two. The door in this case 

 may perhaps be considered as of the cork type, 

 thougli it is very thin, for it does fit into the mouth 

 of the tube, which is bevelled to receive it. 



These nests were forwarded with their living occu- 

 pants {Cteniza \_Actinopiis] {Bclifcatorius) from Tangiers 

 to Prof. West wood, who describes the nests as being 

 " about four inches deep, slightly curved within, about 

 three quarters of an inch in diameter, the valve at the 

 mouth not being circular, but rather of an oval form, 

 one side where the hinge is i^laced being straighter 

 than the other. The valve is formed of a number of 

 layers of coarse silk, in the upper layers of which are 

 imbedded particles of the earth, so as to give the 

 cover the exact appearance of the surrounding soil, 

 the several successive layers causing it, when more 

 closely inspected, to resemble a small flattened oyster- 

 shell.^ 



The resemblance between this nest and that of the 

 West Indian species is the more interesting as Prof. 

 Westwood says that both belong to the same genus, 

 {Cteniza or Actinojjus of different authors,) and are so 

 closely allied as to present scarcely any important 

 distinction but that of size. 



We shall find, however, on comparing the nests of 

 these trap-door spiders and their occupants, that we 

 cannot as yet make any rule as to the kind of nest 

 which we may expect from a given spider. 



* Observations on the Species of Trap-door Spiders, in Trans, of Entomo- 

 logical Soc, Loudon, 1841-3, vol. iii. p. 175. 



I wish to take the present opportunity of thanking Prof. Westwood for 

 having afforded me special facilities for examining this and other specimens 

 forming part of the very valuable collections under his care at Oxford. 



