CUVIER. 523 



D. shell turbinate, the aper- 



Murex, Voluta, 

 Strom bus, Oliva, 

 Cassis, Cypraea, 



ture channelled 



Buccinum, Conus. 

 ACEPHALES 



A, A. naked Ascidia, Biphores, 



,. 7 7 fOstrea, Anomia, 



B. A. conchiferous and apod-] G ,', -p 



J7 7 J 77 . f i bpondvlus. Jrecten. 



ous, the shell inequivalve I pj 



| Lima, Tellina, 



ri 7 . - 7 ., 7 Perna, Cardium. 



L. .4.. cone hirer ous and with A ->.- i T\/T 



f . A j 7 Avicula, Mactra, 



a /oo*, ffo eafoe* *? WC M Mvtilus Venus 



7,7 77 /? .7. _? \ 1VJ.V Lllllo. V clllio. 



and tte fefe* of the mantle ^ ^^ 



opemn front . . . . ^^^ Arca _ 



VUnio, 



D. A. conchiferous and with\ 



a foot, the valves equal, the i -011 



7 77 * \ *i j [Sol en, Pholas, 



she ii qapinq at both ends, h** m i 



.7 7 i r /, 7 , 7 7 Mya, Teredo. 



the lobes oj the m,antle dose 



in front ' 



E. A. conchiferous and apod-\ 



ous, furnished with two J. Terebratula, Orbicula. 

 fleshy ciliated spiral ten- \ Lingula. 



tacula 



E. A. testaceous, furnished. 



with a number of jointed] A ^.~ ^> , 



^ -T T jr i LAnatiia, J3alanus. 

 and ciliated tentacula ar-\ 



ranged in pairs . ) 



There are, you perceive, three primary sections of equal 

 value, and their characteristic names are for the first time in- 

 troduced into science. In preceding systems the Cephalo- 

 pods were considered to be constituents of the order of soft 

 worms, while the Nautilus and Argonauta were members of 

 the order Testacea. The division of the Gasteropods into 

 two subsections from the absence or presence of a shell was 

 not a happy one ; and the unnatural result was to remove 

 the Limax far away from its near relative the Helix. The 

 claims of the Thalides and Lernaea to a place in this order 

 were subsequently proved to be unfounded. The arrange- 

 ment of the testaceous Gasteropods is borrowed partly from 

 Linnaeus and partly from Adanson ; and Poli professedly 

 supplied the characters on which Cuvier distributed the Bi- 

 valves into their families. He was more original and acute 

 when he embodied with them the naked Acephales, although 

 it is probable that he may have found the hint of their 



