AN INGENIOUS DWELLING 



it belonged to I am therefore unable to say ; probably it was 

 the Cteniza cedificatoria, for though the lid of its nest fitted 

 into the tube, it was not so stoutly built as the ordinary 

 cork lid, and was rather oval in outline. 



So far we have only considered the very simplest kind of 

 habitation that is to say, nests consisting of a single 

 chamber closed by a single door. Many spiders, however, 

 construct dwellings of more elaborate architecture, the first 

 step in advance being the addition of a second door part way 

 down the tube. This style is affected by Nemesia Eleanora^ 

 of the Riviera, who places a wafer at the top of the tube and, 

 from two to four inches below this, a solid underground 

 door of earth encased in silk. The upper door conceals the 

 aperture of the nest, while the lower one, which opens in the 

 opposite direction, that is to say downwards, serves for 

 resistance. The inner door is horseshoe-shaped, and lest it 

 should be moved too far up when closed, or become jammed 

 and thus imprison the spider in her own nest, she ingeniously 

 attaches a silk gusset to it on each side. 



The next advance is made by those spiders which dig a 

 side gallery to the burrow and place the second door at the 

 junction of the two tunnels. The scheme of some of these 

 branched nests is very complicated, and requires such nice 

 adjustment in being carried out that we seem to reach at 

 this point the very acme of animal ingenuity. On the right 

 of our picture there is represented a beautiful example of 

 such a nest made by Nemesia Manderstjemce, a species which, 

 like the last named, is found in the Riviera. This nest is 

 shaped, roughly, like a St. Andrew"^ cross. The inner door, 

 which is tongue-shaped and has a tab at the end which 

 serves as a handle, is hung from the point of the V-shaped 

 mass between the two upper arms of the X, and can be 

 swung at will either against the point of the A between the 



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