152 PROCEEDINGS OP THE ACADEMY OP 



That of Electrophorus will be appropriate. This change is the less to be re- 

 gretted, as the nomenclature of carapus is in a confused state, that name having 

 been previously applied by Rafinesque to a species of the genus Fierasfer. Mr. 

 Gill gave an enumeration of the genera of Gymnotoids, admitting the genera 

 Electrophorus, Gymnotes, GUI, (Gymnotus sequilabiatus. Humb.,) Gymnotus, Art., 

 (=Carapus,) Sternopygus, M.T., Hypopomus, Gill, {Rhamphichthys Mullcri, Kaup,) 

 Rhamphichthys, M. T., Sternarchus, Schneid., and Sternarchorhynchus, Cast. Mr. 

 Gill concluded by suggesting that the Gymnotoids were perhaps related to 

 the Nematognathi, and remarked that he knew several undescribed species. 



Mr. Gill next called attention to the fact that the genus for which the name 

 Melantho had been recently accepted from Bowdich, had long before been 

 characterized under the name Campeloma by Rafinesque. In June, 1819, in 

 the 88th volume of the Journal de Pbysique, (p. 423,) that type is introduced 

 in the following terms : 



(26) Campeloma. Test ovale. Ouverture ovale, base tronquee, lievres r6- 

 flechies, flexeuses, unies en pointe poste'rieurement. Point d'ombilic. Ani- 

 mal inconnu. J'en ai une seule espece trouv^e dans l'Ohio. C. crassula. 4 

 tours de spires contraires, sommet aigu, test epais, ouverture plus de la moitie 

 de la longueur totale. 



This diagnosis is evidently only applicable to a Viviparoid, and was doubt- 

 less founded on a reversed specimen of the Paludina ponderosa of Say, or a 

 closely related species. The name has indeed been referred, by the erudite 

 Hermannsen, to the synonymy of Melanopsis, and in this he has been followed 

 by the brothers Adams, but the diagnosis, as well as the habitat, cannot sup- 

 port such a reference. 



In advance of the publication of the generic name Campeloma, Rafinesque 

 had proposed a new genus Ambloxis in the third volume of the "American 

 Monthly Magazine and Critical Review," (p. 355, Sept., 1818,) which was also 

 doubtless intended for the Paludina ponderosa and its congeners,* but the in- 

 sufficiency of his generic diagnosis, as well as the want of connection with 

 any described species, will prevent its adoption. 



The speaker remarked that he would not attempt to enumerate the species 

 of Campeloma, as he could not agree with previous authors regarding their 

 limits, and had not the material to arrive at a satisfactory opinion himself ; 

 he could therefore only refer to the genus an assemblage of forms represented 

 by the same specific names as were formerly placed under Melantho, after the 

 exclusion of Paludina Elliottii of Lea, which probably belongs to the genus 

 Lioplax. The names referred to the synonymy of the other species mentioned 

 under that genus appear to represent forms of the genus, with the exceptions 

 of Paludina cornea, Val., and Lymnula ventricosa, Raf. The former name was 

 doubtless proposed for the Lioplax subcarinata, having the " sutures deeply im- 

 pressed," and the " rampe " around the spire being especially characteristic 

 of that shell. The Lymnula ventricosa was probably founded on Anculosa prae- 

 rosa, or an allied species. 



June 14th. 

 Vice-President Bridges in the Chair. 



Twelve members present. 



A paper was presented for publication entitled " On the Influence 

 of the Earth's Atmosphere on the Color of the Stars." By Jacob 

 Ennis. 



* III. G. Ambloxis. Univalve. Shell thick oboval; mouth oval, rounded at the base, obtuse 

 above", with a thick appendage of the lip ; columella flexuou*; a small rugose umbilicus. 2 species 

 1. A. eburnea; 2. A. ventricosa, Kaf. 



[June, 



