266 Mollusca of Middlebiiry, Vt. and Vicinity. 



Art. IV. — Catalogue of the Mollusca of Bliddlebury, Vt., and 

 vicinity, with observations ; by C. B. Adams, Prof. Chem. and 

 Nat. Hist. Middlebury College, Memb. Bost. See. Nat. Hist. 



The utility of catalogues of species, which inhabit distant 

 parts of this country, as materials for ascertaining their geograph- 

 ical distribution, need not be urged. Even a single local cata- 

 logue cannot but be of interest and utility. It is obviously im- 

 portant that the stations and the abundance or scarcity of the 

 several species should be designated. Such catalogues should 

 also be drawn up by those whose residence in the region enables 

 them to make numerous observations at all seasons, to detect the 

 rare species and those which appear only for a very limited time 

 during the year. 



In obtaining materials for the following catalogue, my acknowl- 

 edgments are due to Prof. George W. Benedict, of Burlington ; 

 also to Messrs. K. Prescott, Luther H. Sheldon, and M. W. John- 

 son, who have been my assistants in the department of Natural 

 History, and who have detected some of the rare species, which 

 might otherwise have escaped search. That other species may 

 yet be found is by no means improbable, for a species, whose 

 habitat should be as circumscribed as that of Vitrina pellucida, 

 Drap., (see following remarks.) appears to be in this vicinity, may 

 elude the researches of many years. Bat after the careful search, 

 which has been made in various places and in every station, es- 

 pecially by my assistants, it cannot be expected that any important 

 additions will be made. 



Melania. 

 M. depygis, Say. It is remarkable that no species of the fam- 

 ily Melaniana occur in the New England States, with this single 

 exception, although some are abundant in New York. This spe- 

 cies occurs here only in Lake Champlain, where it was first found 

 by my friend Prof. George W. Benedict, in Burlington. It is 

 very rare. I have found several imperfect specimens, and but 

 one with the animal, at Shoreham. 



Paludina. 

 P. decisa, Say. ^ This species, so common in the streams and 

 ponds of New England, occurs plentifully in Otter Creek, but 



