420 



PROCEEDINGS OF THE ACADEMY OF 



[Part 11 



la, 46, are redrawn. The valve shown in fig 45 a, h, c, may be taken 

 as type of the species and genus. The lateral teeth described and 

 figured by Gabb do not exist, the surfaces where they would stand 

 being flat. The hinges of small Leptonid bivalves are hard to make 

 out, and we attribute Gabb 's mistake to the use of a low-power hand 

 lens, instead of the compound microscope. 



The external surface shows an extremely minute radial rugosity, 

 or irregular lineolation, under high magnification. Concentric 

 sculpture is very shght. The prodissoconch has a circular outline, 

 like that of Sportella (fig. e) . 



Length 6.2, alt. 4.2 mm. (Fig. 45 a). 



It is plain that the species is not a typical Erycina; the hinge being 

 more like Pseudopythina or Sportella. Not being expert in the study 

 of Leptonacea, the species is left under the original generic name. 



Fig. 45. Neceromya quadrata Gabb, a, b, interior and dorsal views of right 

 valve, type; c, enlarged cardinal detail of same;d, e, interior and dorsal 

 views of a smaller left valve. 



Type no. 2787 A. N. S. P. 



CARDIIDAE. 



We may note in this connection that by a typographical error 

 Cardium durum was spelled durun in Proc. A. N. S. Phila. 1912, p. 

 516. It was correctly spelled on pp. 501 and 519. 



Cardium (Trachycardium) domincanum Dall. 



Cardiuin {Trachycardium) dominicanum Dall, Trans. Wagn. Inst., iii, p. 10827. 



pi. 48, fig. 16. 

 C. {Trachycardium) subelongatum Sby., Gabb, Trans. Amer. Philos. Soc, xv, 



p. 250. 



