Perkins.] 146 [November 3, 



Cumingia Sowerby, 1833. 



Cumingia tellinoides Conrad, Journ. Acad. Nat. Sc, Vol. 

 Vii, p. 234; Gould, Invert. Mass., p. 5Q, fig. 34; De Kay, Moll. 

 jST. Y., p. 233. 



Very rare. 



MACTRID^. 

 Mulinea Gray, 1837. 



Mulinea lateralis Conrad, Am. Journ. Conch., Vol. in, pt. in, 

 p. 31, App. Mactra lateralis Say, Am. Conch., p. 101, 1822; Gould, 

 Invert. Mass., p. 54, figs. 34, 35; De Kay, Moll. N. Y., p. 230, pi. 

 Xxix, fig. 287. Mactra rostrata Philippe, Abbild. in, 138, pi. iii, fig. 

 6, 1845. Mactra corbuloides Desh., Reeves's Conch., fig. 103 (teste 

 Conrad) . 



Obtained abundantly by dredging, but usually not common on 

 shore. In the fall of 1868, however, great numbers were thrown 

 upon the beach, forming long ridges. Animal white ; mantle open ; 

 foot tongue-shaped; when fully extended, as long as the shell; siphons 

 united, fringed at the ends, where they are scarcely distinct, the ven- 

 tral extending a little beyond the dorsal; palpi long, pointed, falcate. 



MEASUREMENTS. 



Length of shell 16.4 mill. Breadth 12.8 mill. 

 " siphon 4 " "5 " 



" foot 16 " (extended). 



Hemimactra Swainson, 1840. 



Hemimactra SOlidissima Conrad, Am. Journ. Conch., Vol. 

 Hi, pt. in, p. 32, App. Mactra solidissima Gould, Invert. Mass., p. 

 51; De Kay, Moll. N. Y., p. 229, pi. xxix, fig. 286. Mactra similis 

 Say, Am. Conch., p. 101, 1822; Gould, Invert. Mass., p. 52, note; 

 De Kay, Moll. N. Y., p. 230. 



Not very common, found only outside the harbor. Animal white; 

 mantle open; gills large, thin, nearly equal; foot moderately large; 

 when extended, as long as the shell, tongue-shaped; when contracted, 

 rhomboidal, notched in the middle of the lower margin ; palpi very 

 long, narrow; siphons short, distinct only at the end; openings 

 frinjred. 



