22 PHYSA. 



appear to suffer from a high temperature, as 

 we find from the remarks of Mr. Lea.* When 

 disturbed by each other, or by extraneous 

 bodies, they whirl the shell about in such a 

 manner as to convince the observer that it is 

 a peculiar mode of defence. 



This genus was first called Bulinus by Adanson, whose 

 name has been retained under the form Bidimus, by 

 Bruguiere, and a few others; but Draparnaud's name pre- 

 vails so universally at the present day, that nothing but 

 confusion would result from a return to the first. Besides, 

 the rule of priority, which must be so rigidly enforced 

 with specific names, is adopted with greater latitude, when 

 genera or families are concerned; because naturalists can 

 not allow the science to be tramelled here, by bad, inap 

 propriate, or barbarous names; although it is proper, as far 

 as practicable, to adopt those which were first proposed 

 A bad specific term affects but one species, whilst an im 

 proper generic or family name, may affect hundreds. 



Adanson will have ample justice, if he be cited for Plan 

 orbis coretus, and Physa bulinus, simply because he re 

 jected the Linnean nomenclature; preferring one which he 

 constructed with the assistance of the niggers of Senegal 

 An author who is not struck with the absurdity of call 

 ing a genus of shells apple snail, objects to such names 

 as bobo, used by Adanson; names, however, which are not 

 worse than physe des mousses! or horny coil shell! 



* Tr. Am. Phil. Soc, vol. vi. p. 18. 



