25 



The stomach is that of a true ruminant. The paunch, which 

 is of great size, compared with the digestive cavity of the sto- 

 mach, has a large portion of its surface, as in the camel, provided 

 with sacs, which open into the general cavity by a narrow mouth, 

 and capable of retaining water. The necessity for this arrange- 

 ment is not exactly understood, as the lama does not generally 

 inhabit desert regions, but places supplied with water. 



The Corresponding Secretary read a letter from Dr. 

 James Lewis, of Mohawk, N. Y., thanking the Society for 

 his election as Corresponding Member, and transmitting a 

 description of a new species of Shell, Cyclas crocea, as 

 follows : 



Cyclas crocea Lewis. 



Shell small, fragile, and translucent; outline simple, rounded, 

 without angles ; beaks nearly central, full, not large, elevated 

 conspicuously above the gently curving hinge margin ; posterior 

 curve distinct from hinge and basal margins, forming a segment 

 of a circle of a radius three times longer than the radius of the 

 anterior curve ; the posterior is separated by a somewhat abrupt 

 turn from the basal margin, which extends forward in a con- 

 stantly diminishing curve, and blends with the curve of the 

 anterior extremity ; the valves are rotund rather than compressed ; 

 surface marked with distinct striations, in some specimens reticu- 

 lated with faint or obsolete radiate scratches ; surface of young 

 shells shining ; adults frequently obscured by a thin ferruginous 

 film. 



Cardinal teeth, in left valve, two, very projecting ; in right 

 valve not discernible. Lateral teeth delicate, prominent and 

 laterally extended, not elevated above the margin of the right 

 valve. 



Color. Young specimens yellowish ; adults, orange, with 

 zones of gray and yellow, which are sometimes retained in the 

 dried shells. Young shells dried become nearly colorless, or of 

 a bluish gray. Animal colorless; tubes of the siphon very wide, 

 forming an important distinguishing feature. 



Dimensions. Long. .275 inch. ; lat. .165 inch. ; ah. 245 inch. 



