1" DR. P. P. CARPENTER ON THE SHELLS OF PANAMA. 



203. Cerithiiim pnuperculum is a good, new species of ChrysalUda. 

 The Professor probably did not recognize the Chemnitzoid apex and 

 the Odostomoid plait. The following alterations may be made in 

 the diagnosis: — Shell pale orange [not horn], with six [not five] 

 keels on the spire ; spiral ridges anteriorly fainter [not obsolete] ; 

 apex sinistral [not acute], of three Paludinoid whorls, the last large 

 in proportion ; columella effuse [not canaliculated], with a long, 

 slendei', slanting plait. 



204. Cerithium pulchrum^Cerithidea p. A distinct and truly 

 beautiful species, seldom obtained by collectors. 



205. Cerithium reevianiim = Cerithidea montagnei, M. 394. 



206. Cerithium vcdidum-=Cerithidea varicosa, M. 395. The 

 Southern shells, in all their change*, present such a different aspect 

 from the Gulf specimens, that I am inclined to regard the form Ma- 

 eatlanica as distinct, of which ('. albonodosa may prove a variety. 



207. Triplioris alternatus, M. 391. 



208. Triphnris inconspieuus is scarcely even a variety of the last; 

 and does not differ so much as the specimens described under the 

 same name, M. 392. 



209. Tripkoris ivfrequens is not the shell described, under the 

 same name, M. 393, but is the Cerif.hiopsis tuberculoid es, M. 557. 

 It would have been strange if I had recognized the shell from the 

 diagnosis ; for both of the specimens are dextral. The apex is nearly 

 smooth. I forbear to redescribe nos. 392, 393 of the Maz. Cat., 

 as they were' separated principally in deference to Prof. Adams's 

 authority, until more numerous specimens should have been examined. 



210. Turritella banksii^=T. goniostoma, jun., M. 379. 



211. Ccecum dim imitum = Caecum Jirmatum, jun., with numerous 

 close rings. All the Professor's specimens of this genus were dead ; 

 tnost of them pierced by Proboscidifers. They fully confirmed the 

 judgments I ventured to form of them in the Maz. Cat. and in the 

 " Monograph of the Csecidte," P. Z. S. 1858, p. 413 ei seq. 



212. Ccecum eburneum = C. firmatum. The rings vary from 

 twenty-six to thirty-three. 



213. Ccecum firmatum, M. 368. Add to the diagnosis in Maz. 

 Cat. p. 320, last line, " operculo vix concavo, suturis minus dejinitis." 



214. Ccecum lave. The two specimens are too worn for identifi- 

 cation, hut will pass sufficiently for the species described under the 

 game name, M. 372. 



215. Ccecum laqueatmn. A good species of the Elephantulum 

 group : v. Maz. Cat. p. 315, and P. Z. S. loc. cit. p. 420. 



216. Ccecum monstrosum = C. Jirmatum in the adolescent stage. 



217. Ccecum parvum turns out, as was expected, to be=C. undo' 

 turn, M. 371. The unique specimen is stunted and dead. 



218. Ccecum pygmxum is a small but nearly adult C. Jirmatum. 



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