327 



out bnt nine instances of its known occurrence in the waters 

 of Europe. 



Mr. W. G. Binney stated that he had received, froni a gen- 

 tleman connected with the Army of the Cumbedand, a 

 species of mollusk wliich had the shell of 3Ielania, with the 

 operculum of a true Melantho ; and he was led to suspect 

 that 7nany of the species which had been described as be- 

 longing to Melania would prove to be Melanthos on exami- 

 nation of their opercula. In alluding to the erosion of shells, 

 Mr. Binney stated that he had seen Melanias, which he had 

 kept in confinement, eating the apices of their own shells. 



Dr. Gould said that he had seen a similar case in ourLym- 

 nasas, but remarked that this was by no means a satisfactory 

 explanation of the erosion in all mollusks, as, for instance, 

 in Unios ; and it was noticeable that no erosion took place 

 among the shells living on coral reefs, or in fresh waters well 

 saturated with lime. 



Dr. Pickering stated that erosion took place, to a remark- 

 able degree, in the shells found in warm springs. 



Mr. A. E. Verrill presented specimens of Matricaria ino- 

 dora (Pyrethrum inodorum Hooker) and Sedum rhodiola 

 from the vicinity of Eastpoi't, Me., neither of which have 

 before been considered as belonging to the flora of the 

 United States. The first was found in considerable abun- 

 dance along the roadsides at Eastport, and also at Grand 

 Menan : its previous localities were Lake Huron (Dr. Todd), 

 York Factory (Drummond), and northward to Great Bear 

 Lake (Richardson). The second species was found growing 

 on the high, trappean clifis at Quoddy Head, the extreme 

 eastern point of the United States. It has long been known 

 upon the neighboring islands of Campo Bello and Grand 

 Menan. 



Mr. Alpheus Hyatt was elected Curator of Conchology. 



