NEW MELANIDCE OF THE UNITED STATES 245 



Genus SCHIZOSTOMA. 



It will be observed tbat I have here adopted my first name {Schizostoma) for the 

 division of those Melanidce which have a cut or fissure in the upper portion of the 

 last whorl. This name I proposed in December, 1842. Subsequently finding that it 

 was used by Bronn in 1835, I abandoned it, and proposed the name of Schizochilus 

 as a substitute, (Obs. on the Genus Unio, v. 5, p. 51, 1852, and Trans. Am. Phil. 

 Soc. 1852). I am now satisfied that Bronn's name was applied to the same genus — 

 Euomphalus — which Sowerby established in 1814, (Min. Conch, tab. 45). This 

 evidently liberates my original name, and Herrmannsen, in the appendix to his " Ge- 

 nerum Malacozorum," very properly restores it. It was supposed that this was the 

 Melatoma of Swainson, and Mr. Anthony adopted this name. But it is evident that 

 Mr. Swainson's Melatoma is not my Schizostoma. By reference to his figure (Mala- 

 cology, p. 342, f. 104) it will be observed at once that there has never been observed 

 in the United States any of the group of which that figure is the type, while it is 

 known that they exist in the islands of the Indian Ocean. Mr. Swainson says 

 (p. 202) that his Melatoma was " founded upon a remarkable Ohio shell " sent by 

 Rafinesque. Now, as no member of the family Melanidce with a cut in the lip has 

 ever been found in the Ohio, where such hosts of active collectors have since pursued 

 their investigations, it is perhaps beyond the bounds of possibility that the specimen 

 sent by Rafinesque, so eminently careless and reckless as he always was, should ever 

 have been found there. Indeed, if the specimen figured was sent by Mr. Rafinesque to 

 Mr. Swainson, then the question would arise whether it had not been obtained by 

 Mr. R. from some dealer or collector, who may have obtained it from Asia. I have 

 no doubt of the Melatoma costata, which Mr. Swainson has figured, being exotic, and 

 belonging to a group probably from the Philippine Islands. Mr. Anthony says, page 

 64, Proc. A. N. S. 1860, that "it may be doubted whether Mr. Lea's first name will 

 not eventually prevail, since, before he published Schizostoma, Bronn's genus of the 

 same name had been called a synonym of Bifrontia, Desh." And that " H. and A. 

 Adams (Gen. Rec. Moll. 1, 105) do not appear correct in giving preference to Gyro- 

 ioma over Schizostoma, Lea," &c. Notwithstanding this, Mr. Anthony in this paper, 

 where he describes nine supposed new species of this genus, adopts the generic name 

 of Gyrotoma. It may be added here that Dr. Gray, in his Genera, of Recent Mollvsca, 

 gives Melatoma to Mr. Anthony, not to Swainson, while he does not notice the name 

 of Sc7iizostoma. Mr. A. does not pretend to claim it, of course, but adopts Gyrotoma, 

 Mr. Shuttleworth's name, proposed in 1845, which being three years later cannot 

 have precedence. 



The genus Schizostoma seems to be capable of being divided into two natural 



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