THE SPIDERS. 335 



ever, about this arrangement is that any enemy penetrating 

 into the nest is most completely deceived, for when the subter- 

 ranean door is so situated that it shuts off the main passage, 

 the invader in pressing onwards is not in the latter but in 

 -the side cylinder, and as he discovers nothing here, but 

 imagines himself to be in the main cylinder, he must retire 

 with all his work for .nothing. 



But that which complicates everything to a specially high 

 degree is the circumstance that this side tunnel, as a rule, is 

 only found in the nests of the younger spiders, while in the 

 older ones it is generally stopped up with earth and rubbish, 

 and is, therefore, easily overlooked in investigating the nest, 

 or else is not regarded as being present. This curious state 

 of affairs is explained either by the fact that the side cylinder- 

 is intended as a protection against an enemy which the older 

 and stronger spiders have no need to fear, or that the older 

 spiders neglect this precaution when the time is come that 

 they lay no more eggs and, therefore, no longer need any 

 special protection for them. As Moggridge, further, found 

 many remains of slain insects in the doubtful cylinder of 

 old nests, it is also possible that it is intended to serve as 

 a place of deposit for these remnants. 



The nests of X. 3fanderstjern.ce, for the rest, exactly 

 resemble those which Moggridge investigated at Mentone 

 and described. 



To show, lastly, how various are the transitional forms and 

 gradations so important in deciding upon the gradual origin 

 of the forms of nests, Moggridge also alludes to the similar 

 buildings made by other genera of spiders. Lycosa narbo- 

 nensis, a spider of Southern France much resembling the 

 Apuleian tarantula, and belonging to the family of the 

 wolf spiders, makes cylindrical holes in the earth, about 

 one inch wide and three or four inches deep, in a perpen- 

 dicular direction ; when they have attained this depth they 

 orun further horizontally, and end in a three-cornered room, 

 from one to two inches broad, the floor of which is covered 

 with the remnants of dead insects. The whole nest is lined 

 within with a thick silken material, and has at it.s opening 

 closed by no door an above ground chimney-shaped exten- 

 sion, made of leaves, needles, moss, wood, etc., woven together 

 with spider threads. These chimneys show various differ- 

 ences in their manner of building, and are intended chiefly, 



