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" the web of a Bermuda spider. It is as strong as to 

 snare a bird as big as a thrush : 'tis here wound upon a 

 a paper, like new silk." We remember to have found, 

 in our rambles through the Pontine marshes, a spider's 

 thread, white as snow, and like ravelled silk, of con- 

 siderable cohesion. In the Magazine of Natural His- 

 tory we have described a beautiful conical structure 

 discovered in South America, and, in all probability, 

 the workmanship of the mygale avicul. The mygale 

 cementaria, a native of Jamaica, burrows in the earth 

 like a rabbit, forming a cylindrical cavity from twelve 

 to fifteen inches in depth : like the upholsterer bee, it 

 lines its walls with silk tapestry ; it also constructs a 

 valve or trap-door of silk, opening from within, and 

 closing the aperture by its own weight. In the fens 

 of Norfolk may be found a large spider, which forms 

 a raft for catching its prey : this raft is constructed 

 of a ball of weeds, and is about three inches in 

 diameter : the insect takes possession of the " eme- 

 rald isle," and thus commits itself to the stream. 

 The aranea aquatica constructs a subaqueous abode 

 by attaching threads to the stems or leaves of aquatic 

 plants, and smearing the interstices of the meshes 

 over with some transparent glutinous matter, similar, 

 we think, to that used by the caddis worm in the 

 construction of its leafy dwelling : the diving bell is at 

 length finished, and the introduction of air, brought 

 from the surface and introduced beneath, expels the 

 water ; and here, in its crystalline subaqueous domi- 

 cile, it devours the prey at leisure it hunts for some- 

 times on land, and where none of its congeners will 

 care to follow and contend for possession. This cu- 

 rious fabric is filled with air precisely in the same 

 manner as the chemist supplies his deflagrating jar or 

 bell-glass over the shelf of the pneumatic cistern ; and 



