THE STOMAPODA. 391 



animals, which float about, in the ocean, upon marine 

 plants ; and it is supposed that it was one of these which 

 indicated to Columbus, some days before his discovery, the 

 proximity of the New World. The sub-parasitical Pin- 

 notheres are also singular, from inhabiting, at certain sea- 

 sons, the bivalve shells of some of the Mollusca. Among 

 the curious genera which form the passage from the 

 Brachyura to the Macroura, or large- tailed division of 

 the decapod Crustacea (the lobster), we find those in 

 which the enlarged tail has not yet become the chief 

 organ of progression, by means of its violent and sudden 

 concussion ; and among these, the Pagurus, or hermit 

 lobster, is worthy notice, from its habit, in consequence 

 of its tail being always soft, of seeking for its protection 

 some univalve shell, wherein it buries it; and these shells, 

 with its progressive enlargement, it has the instinct to 

 change. The allied jBjt^ms, which, from its size, cannot 

 find shells convenient for its reception, lives naked, and 

 has the habit of dwelling for a long time, like the land 

 crabs, in cavities of rocks and burrows of the ground. 

 The normal Macroura contain the large Palinurus 

 homarus, or sea crayfish, which has not didactyle claws; 

 the Astacus Gammarus, or lobster; the Astacus fluvia- 

 tilis, or river crayfish, — both with large anterior chelated 

 claws ; the former marine, and the latter inhabiting the 

 fresh water ; the Crangon, or shrimp ; and the Palcemon, 

 or prawn, — delicacies for the breakfast table ; and multi- 

 tudes of others. 



(353.) Among the Stomapoda, or sea mantises, — 

 named thus from their spined raptorial anterior legs, — 

 occur Squilla and its allies ; and near these, but with- 

 out such legs, we find the genus Phyllosoma : their 

 kaf-like bodies, indicated by their name, are as flat 

 and transparent as a piece of stamped mica ; their head 

 is disproportionately large, and abdomen equally small. 



(354.) The second division of the Crustacea, the 

 Edriophthalma, or those with sessile eyes, contains three 

 groups ; — the Crustacea Amphipoda, which constitute 

 the various generaof those compressed shrimp-like jump- 



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