66 On the Identity of Cyclas elegans, &c. 



country. Its foreign analogue is the P. sinualum of Bourgui- 

 gnat. See Petit's Jour, for 1852, page 49. 



3. Pisidium IVoveboracense* 



CABINET OF THE NEW YORK LYCEUM OF NATURAL HISTORY. 



Plate I. Fig. 3, a, b. c. 



Shell large, high, not much elongated, full ; beaks prominent 

 and large ; anterior margin elongated, posterior one curved. 

 Sulcations not very light. Color varying from greenish-yellow 

 to brown. Interior light blue. Length 0.35, Breadth 0.18. 

 Diam. 0.13 inches. 



Habitat. "Washington County, JST. Y. (Ingalls), and Herki- 

 mer County, 1ST. Y. (Lewis). 



Remarks. This is one of our largest American species. Com- 

 pared to the P. dubium, it is less elongated, less robust, less 

 heavily marked, and differently colored. Found in plenty. 



X. On the Identity of CYCLAS ELEGANS Adams, with CYCLAS 



KHOMBOIDEA Say. 

 By TEMPLE PRIME. Head September 5, 1853. 



In 1822, Say published as follows, in the Jour, of the Acad. 

 of Nat. Sci., vol. ii., page 380 : 



" Cyclas rhomboidea. Shell transversely orbicular, rhombiform, sub- 

 equilateral, pale with elevated somewhat transverse lines, umbo not promi- 

 nent. 



