DR. P. P. CARPENTER ON THE SHELLS OF PANAMA, H 



192. Mnngelia sulcosa is the true Qolambella s of Sbv, 



193. Cerithium adustuin = C. maculosum, M. 381. 



194. Cerithium assimilatam^Gerithiopsis a., M. .563. , 



195. Cerithium bimarginatum^Cerithiopsis b. A good species; 

 but I could not detect the "intermediate raised line." The apical 

 whorls are almost smooth. The "prominent spiral fold" on tlie 

 columella is simply that which bounds the recurved canal. 



19(). Cerithium famelicum. Confusion has arisen from the Pro- 

 fessor having sent to .Mr. Cuming as his type a shell which does not 

 answer to the diagnosis, and which is described as (? var.) mediolmve, 

 M. 382. Ten specimens are retained in the Amherst Museum, of 

 which eight are of the uncinatuin type, =M. 383, and two of the 

 Cumingian. G. uncinatum, being an old species, is probably from 

 the Atlantic or E. Indies : if this should prove identical, the name 

 /amelicum must be dropped; if distinct, retained for the west coast 

 uncinoids, according to the diagnosis. After an e-tamination of a 

 large series of specimens collected by j\lr. Xantus at Cape St. Lucas, 

 I am confirmed in the belief that the Cumingian shell is a distinct 

 species, which must stand as C. mediolesve. 



197. Cerithium ffemmatum=Rhinoclavis ffemmatus, M. 389. So 

 much confusion has arisen from raising specific names to the generic 

 peerage, that whenever a good distinct name has been given, it ap- 

 pears best to retain it — the unbending rule of mere priority for work 

 which is sometimes slovenly, and therefore best forgotten, notwith- 

 standing. 



198. Cerithium ? interruptum, C. B. Ad. (non Mke.=M. 388). 

 Great confusion has arisen from this erroneous determination, as 

 may be seen by comparing the Maz. Cat. in loco with the mono- 

 graph of Sowerby, jun., who has redescribed the southern, higldy 

 sculptured forms of the true interruptum as C. galapaginis. 



198 and 199 are regarded by Messrs. Cuming and Sowerby as 

 varieties of 



200. Cerithium irroratum, Q. B. Ad. (Gld. ipse et MSS., non 

 Old. in Expl. Kxp.) = t!'. stercusmuscarum, M. 387. The aspect of 

 the Panama shells is so different from that of the Mazatlan speci- 

 mens that I did not wonder at Dr. Gould's opinion that they were 

 distinct. He was, however, misled in affiliating the former to his 

 C. irroratum, of which I fortunately discovered the figured type in 

 the Smithsonian Institution, and which proves to be (according to 

 Mr. Cuming) the C. obesum of Sby. sen., from the Phihppines. It 

 is fortunate therefore that the name may be entirely dropped. Some 

 of the specimens of no. 198 graduate suflSciently closely to the Ma- 

 zatlan form; those of no. 199 are intermediate; while those of 

 no. 200 present a stronger but smaller shell, well armed with small 

 nodules, which are not to be seen in the fine Gulf specimens. 



201. Cerithium neglectum= Gerithiopsis n. 

 I'i'l. Cerithium pacijicum. Stet. 



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