NEW FRESH WATER AND LAND SHELLS. 249 



Shell elliptical, smooth, polished, very much inflated, somewhat cylindrical, 

 having transverse green bands; substance of the shell thin; beaks slightly 

 prominent and undulate at the tip; ligament long and very thin; epidermis 

 polished, yellowish, interrupted by green transverse bands, with numerous 

 small rays darker on the posterior slope, where they are very distinct and ca- 

 pillary ; anterior cicatrices confluent; posterior cicatrices confluent; dorsal 

 cicatrices none ; cavity of the shell deep and rounded ; cavity of the beaks very 

 small; dorsal line nearly straight; nacre white and iridescent. 



Remarks. — Mrs. Dunlap^ whose name it gives me pleasure to place to this 

 shell, has favoured me with three specimens of this beautiful Anodonla, all of 

 which have the remarkable green bands mentioned. It has some resemblance 

 to An. Jiuviatilis, with some of the characters of An. Couperiana, (nobis.) It 

 is less oblique than the former species, and more cylindrical, and has the 

 peculiar capillary rays of the latter species. It differs from An. Couperiana, 

 in being a larger species, in being without the gibbous character, in being less 

 rayed and in being thicker, — the nacre is also less blue, there being a slight 

 pinky hue in the Dunlapiana. On the posterior slope on each valve there are 

 two distinct green rays passing from the beaks to the posterior margin. 



