XXXIV 



two and one-half years' priority over Shuttleworth. 

 I entirely agree with Mr. Lea, that Mekdoma, Swain- 

 son, rejDresents an exotic, and not an American, 

 group. Mr. Anthony is ignorant how his name 

 came to be used in connection with Melatoma. It 

 was first so used by Dr. Gray* (perhaps through 

 inadvertence), and afterwards by Mr. Reeve. 



8. Jleseschiza, Lea. 



9. Anndosa, Say. — Lejytoxis, Rafinesque, as al- 

 ready mentioned, is not described definitely enough 

 to justify its substitution for Say's name. Prof. 

 Haldeman, with the aid of Rafinesque's manuscript 

 work, identified the genus and used the name. He 

 has been followed by Messrs. Adams, Brot, and Bin- 

 ney, while Messrs. Lea, Conrad, Anthony, and Reeve, 

 have adhered to the old name, I think that ElUp- 

 stoma, Raf. (Jour, de Phys.) really applies to this 

 genus much better than Lejitoxls, and might be 

 readily taken to represent such a form of it as crassa, 

 Hald. 



Prof. Haldeman proposed a subgenus Mudalia for 

 certain thin species without enamel on the labium, 

 and probably intended to include such globose forms 

 as altUls, Lea, &c., but the only species which he 

 cites under the name, are dissimilis, Say, and tnrgida, 

 Hald., both carinate shells. I am convinced, from 

 studying numerous examples, that the characters 

 of 3Iudalia are not persistent. The globose form 

 of so-called Ancidosm, represented by altilis, does 

 not belong to the family. Mr. Gill has proposed 

 for it the generic name Somatogyriis, and it is now 

 included in Amnicolidce. 



These same Virginia and Ohio thin species, 

 together with the dentate forms, compose the sub- 

 genus Nitocris^ H. & A.Adams, a synonyme, anyhow, 

 and otherwise of no value. Mr. Anthony proposes 

 to me to call such shells as Anculosa nionodontoides, 



*Mr. Anthony never described such a shell as Melatoma altilis, 

 Auth., referred to by Dr. Gray. 



