276. Mollusca of Middlebury, Vt. and Vicinity. 
species is quite common. A species of Limax also occursiof the 
same size. . eS 
ANODONTA. > 
A. Benedictensis, Lea. This 
Champlain, where it is abundant. 
A. cataracta, Say. At Wallingford, Vt.,a very few specimens 
have been obtained. ae , 
Two other species of Anodonta occur, which I hatetnot been 
able to identify with any species known to me. One of them re- 
sembles A. Wardiana, Lea. 
oy, en é 
species occurs only in Lake 
ALASMODONTA. — Pe 
A. arcuata, Barnes. That this species is quite distinct from 
the margaritifera of Europe, I have had an opportunity of seeing 
from a specimen of the latter in the cabinet of Dr. Gould. 
Barnes’s species occurs in Onion river, at Burlington. 2 
A. rugosa, Barnes. 'This species occurs in Otter Creek and 
Lake Champlain, but is not common. . 
A. undulata, Say. This species occurs in Otter Creek. 
* 
Unto. 
U. alatus, Say. Abundant in Lake Champlain. 
U. gracilis, Barnes. Common in Lake Champlain. 
U. compressus, Lea. This species occurs, well characterized, 
in a rivulet a few miles west of this village. In the east part o 
this town are specimens which differ so much from the common 
type as perhaps to constitute a new species. sf 
U. rectus, Lam. This species occurs rarely in Lake Cham- 
plain. : 
U. ventricosus, Barnes. This species is rather common 
Lake Champlain. It is subject to great variations of form. 
U. luteolus, Lam. This species is very abundant in Lake 
Champlain. Its variations in form, although less than in the pre- 
ceding, are considerable. In both, however, the most marked 
are those of sex. a 
U. complanatus, Lea. Very abundant in Lake Champlain and 
elsewhere, but I have not seen one with a white nacre. Rayed 
specimens are sometimes: seen. 
Ihave found in Lake Champlain a single specimen of anothet 
species, which is unknown to me. 
in 
