

32 



LAND AND FRESH-WATER SHELLS OF N. A. [fART IL 



Animal clingy mouse-color, with a slight tinge of purple, covered with 

 numerous microscopic, elongated white spots on every visible part of the 

 suiface, including the mouth and tentacula ; foot of a chocolate color, 

 rather broad, length rather greater than the aperture ; habits sluggish. 

 Cabinets of the Bost. Soc. N. H., Dr. Gould, S. S. Haldeman, J. Gr. Anthony, 

 J. W. Migliels, and C. B. Adams. 



Unity, Maine, discovered by Dr. Milliken of that town, to whom we are 

 indebted for specimens. 



This odd but interesting shell is readily recognized by its rhomboidal 

 aspect, wide aperture, and rather rough and distorted appearance. It is 

 allied to L. caUiscopiitm, Say, but is distinct from that shell by having less 

 whirls by two, and a much shorter spire ; by being wider, and its diver- 

 gence greater by more than thirty degrees. By some it has been supposed 

 to be identical with L. emarginata, Say. This is impossible. L. emargi- 

 nata is much more cylindrical, the divergence of its spire is scarcely half 

 as great as that of our shell ; it is much thinner, and has at least two more 

 volutions. Our shell is also destitute of the " deep emargiuatiou" which 

 distinguishes L. emarginata. (Mighels ^ Adams.) 



Limnaea decollata, Mighels, Proc. Bost. Soc. I, 40 (1841) ; Bost. Journ. 



IV, 4-5, 336, pi. iv, f. 13 (and Adams) (1842). 

 Limnwa catascopium, Haldeman, part, Mon. 52, pi. xiv, f. 1-3 (1842). 



Limnseus clecollatus, Kustek in Ch. ed. 2, 45, pi. viii, f. 

 11-14. 



Fouud around Lake of the Woods, iu Maine and 

 Connecticut. 



Haldeman and DeKay refer this species to L. 

 catascopiuvi. I have given the original descrip- 

 tion and figure above. Xo. 9132, presented by 

 Prof. Haldeman, were by him received directly 

 from Mighels. One is figured iu Fig. 37. 



Fig. 37. 



Liiniliaea coltlinella, Say. — Shell thin, fragile, horn-color ; whirls 

 four, longitudinally wrinkled. Spire prominent, acute. Suture not mueli 

 impressed. Aperture dilated, ovate. Columella much narrowed near the 

 base, so that the view may be extended from the base almost to the in- 

 terior apex of the shell. Length y',, of an inch nearly, of the spire ] inch. 



Inhabits stagnant waters and miry places. Collection of the Academy. 



Animal aquatic, base not so long as the aperture ; dusky, with small 



