xiv NESTS 355 



Doors of the cork type consist of alternate layers of silk and 

 earth. After weaving a covering of silk, the creature brings earth 

 in its jaws and lays it on the top, binding it down with a second 

 layer of silk, and the process is repeated until the requisite 

 thickness is attained. 



The nests are exceedingly difficult to detect, as the spiders 

 take the precaution of attaching leaves, moss, or small twigs to 

 the outer surface of the doors. This does not appear to be the 

 result of intelligence, but a mere instinctive habit ; for if a door 

 be removed and the surrounding earth denuded of moss, the 

 spider will render the new door conspicuous by bringing moss 

 from a distance, and thus making a green spot in the bare patch 

 of earth. 1 



The cork doors fit with great exactness, and there is always 

 to be found on their under surface a notch by which they are 

 held down by the fore-legs of the spider against any attempt to 

 open them from without. 



Many nests with trap-doors of the wafer type are found to 

 have a second and more solid door within the tube. This serves 

 to shut off the lower part of the nest as a still more secure 

 retreat. This second door opens downwards, and the Spider, 

 getting beneath it, is effectually shielded from an enemy which 

 may have mastered the secret of the outer barrier. The nests 

 of some species present still further complications in the way of 

 lateral branches from the main tube. In one case (Nemesia 

 congener} the burrow becomes Y-shaped, and the second door 

 hangs at the fork of the Y in such a manner as to connect the 

 Toottom chamber either with the entrance or with the, branch, 

 which does not reach the surface, but ends blindly. 



Trap-door Spiders are greatly attached to their tubes, which 

 they enlarge and repair at need. They begin burrowing very 

 early in life, and their tiny tubes resemble in all respects those 

 of their parents. Their habits are nocturnal, and little is known 

 of them; an observation, however, on a species inhabiting the 

 island of Tinos in the Grecian Archipelago (Cteniza ariana), by 

 Erber, 2 must not be omitted. This spider leaves its tube at. 

 night and spins a web near at hand and close to the ground. 

 It carries captured insects into its tube, and in the morning 



1 Moggridge, Harvesting Ants and Trap-dour Spiders. London, 1873, p. I'^o. 



2 Verh. Ges. Wien, xviii., 1868, p. 905 (Abstract in Zool. lice, v., 1868, p. 175). 



