l'^ DR. P. P, CARPENTER ON THE SHELLS OF PANAMA. 



203. Cciifhiiim pavpercuJum is a good, new species of Chri/saUida. 

 The Professor probably did not recognize the Chemnitzoid apex and 

 the Oflostonioid })lait. Tiie 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, 

 slender, slanting plait. 



204. Cerithium pidchrum=Cerithidea p. A distinct and truly 

 beautiful species, seldom obtained by collectors. 



205. Cerithium reevianum^Cerithidea montagnei, M. 394. 



206. Cerithium validum^=Cerithidea varicosa, IM. 3fJ5. The 

 Southern shells, in all their changes, present such a different aspect 

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

 zatlanica as distinct, of which C. albonodosa may prove a variety. 



207. Triphoris alternatus, M. 391. 



208. Triphoris inconspicuus 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. Triphoris infrequens is not the shell described, under tlie 

 same name, M. 393, but is the Cerifhiopsis tuberculoides, M. 5.57. 

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

 diagnosis ; for hath 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 Lanksii=T. goniostonia, jun., M. 379. 



211. Ccecum diniituttum=CcBcum Jimiatiim, jun., with numerous 

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

 most 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 Csecidse," P. Z. S. 1858, p. 413 et seq. 



212. Caecum eburneum = C. fii'matum. The rings vary from 

 twenty- six to thirty-three. 



213. Cacum frmatianyM. 368. Add to the diagnosis in Maz. 

 Cat. p. 320, last line, " operculo vix concavo, suturis ininus defnitis." 



214. CcEcum Iceve. The two specimens are too worn for identifi- 

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

 same name, M. 372. 



215. Ccecum luqueatum. A good species of the EJephantuIum 

 group: V. Maz. Cat. p. 315, and P. Z. S. lac. cit. p. 420. 



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



217. Ccecum parvum turns out, as was expected, to be = C uiida- 

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



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



186 



