SPIJDE&S. 



entrance to this excavation is carefully guarded by a lid or door, that moves upon a 

 hinge, and accurately closes the mouth of the pit. In order to form the door in ques- 

 tion, the Mygale first spins a web, exa .tiy covering the mouth of the hole, but attached 



FIG. 150.- TRAP-DOOR SPIDER. 



to the margin by one point only of its circumference. This point, of course, forms the 

 hinge. The spider then proceeds to spread upon the web a thin layer of the soil 

 collected in the neighbourhood of her dwelling, and covers it with another stratum 

 of silk ; layer after layer is thus disposed, until at length the door -acquires sufficient 



FIG. 151 NEST OF 

 TKAP-DOOR SPIDER. 



Fi~. 152. TRAP-DOOR OPENING 

 BY A LEVER. 





FIG. 153. SECTION OF NEST. 



strength and thickness. When perfected, the concealment afforded is complete, for as 

 the outer layer of the lid is formed of earth precisely similar to that which surrounds 

 the hole, the strictest search will scarcely reveal to the most practised eye the retreat 

 so singularly defended. 



As might be expected, there are varieties in the shape and size of these nests. Some 

 specimens, obtained in the island of Zante, have the silken layers of the lid extended 

 into a sort of handle or lever just above the hinge, on pressing which the trap-door 

 opens. 



