MACOMA. 93 



three fourths hich ; height, three fourths of au iuch ; l)readth, eleven 

 twciitietlis of au iuch. 



Sent to nie by Dr. L. :M. Yale from Martlia's Yiuevard. Gull 

 Islaud (Smith). 



It is a })roportionally shorter and broader shell ; but its most ob- 

 vious mark of distinction is the want of an areola l)efore the beaks. 



[Dr. Stimpson remarks : " I have found the differences between 

 this and the preceding species, mentioned by Dr. Gould, to be in- 

 constant." There is much doubt in my own mind also in regard 

 to its title to a separate name, as I have seen no extended series 

 for comparison. The shell figured in Sowerby's Thesaurus is widely 

 different from this, and is probably a South American species. 



Family TELLINID^E, Lateeille. 



Not more than two cardinal teeth on the same valve ; a lateral 

 tooth each side when not obsolete ; ligament on the shorter end ; 

 pallial sinus very large ; animal with long slender separate siphons ; 

 mantle open. 



Oemis MACOMA, Leach. 1819. 



Shell equivalve, sub-ovate, compressed, rounded anteriorly, sub- 

 rostrate posteriorly, slightly gaping at ends, with posterior sub-mar- 

 ginal flexure ; hinge with two small cardinal teeth in each valve ; 

 pallial impression with a deep sinus. Animal with one simple 

 fringe on each side. 



"O^ 



Macoma fusca. 



Fig. 42. 



Shell compressed, ovate-orbicular, sub-equipartite, rounded before and some- 

 what pointed behind; white, covered with a dusky epidermis; teeth, two in 

 each valve, the largest of which is grooved. 



Lister, t. 405, fig. 250. 



Psammolda fusca, Say, Journ. Acad. Nat Sc. v. 220 (1826). 



Sangmnokma fusca, Conkad, Amer. Mar. Conch. 34, pi. 7, fig. 1 (1831). — Stimpson, Sh, 

 of New Eng. 20 ; Tnv. Gr. Man. 2d ed. 21. —Gould, Inv. Mass. 1st cd. 66. — I)b 

 Kay, Nat Hist. N. Y. 212, pi. 32, fig. 304. — Mighels, Bost. Journ. N. H. iv. 317. 



Tellina fusca, Phil. Abbild. t. 3, fig. 3. 



Tellina inconspicun? Sowerby, Zool. Journ. iv. 359. — Gray, Zool. Beech. Voy. 153, pi. 

 41, fig. 6. — Han-ley, in Sowerby, Thes. Conch. 317, pi. 59, fig. 120. 



Tellina Gronlandica, Beck, see Lyell, Tr. Geol. Soc. Lond. 1841, vi. 137, pi. 16, fig. 8. 



