304 SUPPLEMENT 



before the fire in cold water, while alive, for were they to be 

 thrown into the liquor already boiling, the moment they felt 

 the strong impression of the heat, they would break their 

 claws, the preservation of which is a necessary condition in 

 the art of cooking them. When put to the fire in the cold 

 water, they seem to perish without feeling any pain intense 

 enough to cause violent movement or agitation. 



In the large rivers of Russia, such as the Don and the 

 Volga, there are astaci of prodigious size, which are never 

 fished but for the sake of getting the stones above mentioned. 

 When a certain quantity have been taken, they are heaped 

 together to cause them to rot, and when their decomposition 

 is almost complete, they are washed with water. The stones, 

 as being the most heavy, fall to the bottom. These stones, 

 which, for many ages, have enjoyed a very high reputation, 

 and which are still considerably sought after in countries 

 where prejudice and superstition predominate, are no longer 

 esteemed in Europe, but as a little bit of chalk, and if it may 

 still be found in the shops of some apothecaries, it is merely 

 from a remnant of ancient custom. 



The various species of sea astaci have vulgar names, dif- 

 fering from the scientific, in consequence of an error of Lin- 

 najus. Thus the lobster, {homard, in French) is not the 

 cancer Jiomarus of this naturalist, but the cancer marinus. 

 The cancer homarus is a part of the genus Palinurus, of 

 which we shall presently speak. 



We shall next briefly notice that very curious genus the 

 Pagurus. 



The Greeks named generically carcinion, the parasite Crus- 

 tacea, which lodge themselves in the empty shells of the 

 mollusca, and the Latins designated these same animals under 

 a synonymous name cancellL Aldrovandus, Gesner, Rondelet, 

 Swammerdam, and other modern naturalists, preserve this last 

 denomination ; but Fabricius has bestowed that of Pagurus 



