CONCIIOLOGICAL WRITINGS. 81 



T N. G. SULCULARIA. 



109 Sp. Alasm. badium {Sulcularia hadia disc. 1821.) Shell 

 thiu, suboval, truncate obliqually behind, back straight, rounded 

 beneath, outside smooth bay with some faint bands, inside pale bay 

 or rufous iridescent. Length 2-3, diameter and axis 1-4 of the 

 breadth. 



Small streams of the Knobs, rare, one or two inches : tooth obtuse, 

 projection very small. 



110 Sp. Alasm. papyraceum (Sulcularia jyapyracea disc. 1821.) 

 Shell very thin and flat, elliptical, broader behind, truncate crenate 

 with furrows and broad ribs : outside olivaceous a little uneven, 

 inside bluish. Length one half, diameter 2-9, axis one fourth of 

 breadth. 



In East Kentucky. Yery rare ; 2 or 3 inches, tooth short and 

 wide, projection with an oblique fold ; the posterior ribs are seen 

 both outside and inside. 



III. Genus or tribe Lasmonos. 



8 N. G. Lasmonos. Cardinal tooth none, remplaced by a sinus, 

 a flat tubercle, and a decurrent enamel. Lamellar tooth curved 

 following the beak. General form of Ilelaptera with a small coales- 

 ■cent wing. 



Ill Sp. Lasmonos Fragilis disc. 1822. — Shell very thin, 

 depressed, suboval, broader behind, with a small wing, some nodulo- 

 sites behind, outside smooth olivaceous, inside purplish blue. Length 



3-5, diameter and axis 3-10 of the breadth. 



In East Kentucky, very rare, 2 or 3 inches wide. Yery singular 

 shell, which I mistook at first for a Metaptera ; tubercle of the 

 hinge hardly visible, lamellar tooth very long, close to the back, 

 bifid at the end in the left valve. Type of a new Genus 

 which may include other species when sought for in the south 

 west. 



lY. Genus or tribe, Anodonta. 

 112 Sp. Anodonta inflata. disc. 1S22. 



Shell thick, elliptical ; somewhat attenuated behind, very much 

 swelled, summits wrinkled, subprominent, outside olivaceous, 

 wrinkled, inside white iridescent. Length ^3-5, diameter 2-5, axis 

 3-10 of the breadth. 

 F 



