ox CRUSTACEA. 273 



deposition, for a greater or less time. In some the}' are fixed 

 to the false feet by means of filaments, which result from the 

 solidification of the mucus that surrounded them at the 

 moment of their issuing forth ; in others, they ai'e placed in 

 external membranaceous sacs, or in a dorsal cavity. 



In most species of Crustacea, when the little ones are dis- 

 closed, they remain some days near the mother, and place 

 themselves under her tail, as has been observed in some crabs, 

 and in the river craw-fish, or between the leaflets of the gills, 

 as has been remarked in regard to the onisci. 



Most Crustacea are used by us as food. The larger and 

 middle sized species, of which the individuals are numerous, 

 are those which are in most request. Their flesh is nourish- 

 ing, but difficult of digestion, and much of it cannot be eaten 

 with impunity. 



The decapod Crustacea are the only animals of this class 

 which are eaten in Europe. Among the brachyuri, the most 

 esteemed are cancer pagurus, cancer puher, and the mala 

 squinado. As to the C. moenas, it is not so much in request, 

 and its most frequent use is as a bait to catch fish and other 

 Crustacea. Among the macrouri, the palinurus and the lobster 

 hold the first rank in consequence of tlieir size, and then come 

 palcemon j)cn(Ba!<, many species of nika, the river craw-fish, 

 and crangon. These last, which are eaten very much, though 

 more on the continent than in England, are also employed as 

 bait. 



Many of these Crustacea, such as pen(Bus and PaUemon, are 

 salted in some parts of the coast of the Mediterranean, and 

 sent into the East, where the Greeks make an abundant use 

 of them, especially in the season of Lent. 



Formerly the trade in the stones which are found in the 

 stomach of craw-fish, vulgarly called crabs' eyes, was suf- 

 ficiently productive, when these bodies were made use of in 

 medicine as absorbents, and it was particularly from Hungary, 



VOL. XIII. T 



