20 TESTACEOUS MOLLUSCA. 



composed of a rounded tooth which projects forward, and a smaller 

 acute one by the side of it. 3.. 5|. — N. Europe. 1 



M. Cancellata. Conr. Jour. A. N. S. Phil. 7. p. 236. t. 18. 



f. 2. Subelliptical, ventricose, with numerous prominent slightly 



undulated concentric striae ; a slight furrow extends from beak to base, 



posterior side with radiating striae, umbo prominent, anterior side 



short: tooth very erect, dilated, biemarginate. -£. . 2. — U.California. 



M. Semistriata. Nobis in Zool. Pr. 1843. Ovate-oblong, sub- 

 equilateral, tumid, posteriorly rounded, anteriorly attenuated ven- 

 trally and subtruncated at the extremity; white, thin, pellucid; pos- 

 terior area smooth, the central with crowded fine radiating striae 

 which anteriorly become fine ribs and terminate at the anterior slope 

 which is roughened by transverse sublamellar wrinkles: tooth resem- 

 bling that of Arenaria but more oblique. |- . . 1 . —1 have seen but 

 one valve. 



ANATINA. 



Transverse, subequivalve, gaping at one or both ends. Primary 

 tooth naked, dilated, spoon-shaped, somewhat projecting internally 

 and receiving the ligament in each valve. In many species, an 

 affixed lamina or false rib runs obliquely under the cardinal 

 teeth. 



A. Lanterna. Lam. 1. — Born. p. 23. vignette 6. — Solek Spen- 

 gleri, W. t. 3.f. 30. Ovate, rounded at each extremity, and not 

 beaked anteriorly ; very thin, fragile, swollen, pellucid and white. 

 1 .. 2. — Indian Ocean. 



A. Truncata. Lam. 2. (partly) — Del. t. 3.f. 2. Ovate, thin, 

 white, transversely striated, anteriorly subtruncated, roughened by 

 minute raised dots : subnacreous within. — ■ China. ? 



A. Subrostrata. Lam. 3.- — Solen Anatinus. Lin. Gmel. no. 

 S.—D.p. 65.— Ch.f. 46,48.-7?. t. 228. f. 3. — W. t. 3./. 13. 

 Ovate, membranaceous, pellucid, white and very thin gibbous, a very 

 short minute radiating fissure at the beaks : anterior end gaping 

 the more widely and subrostrated. 1^..2. — Indian Ocean and 

 New Holland. 



A. Globulosa. Lam. 5. — Mya Anatina, Gmel. 3221. — D.p. 

 44.— Ch.f. 13 to 16. — W. t. 2.f. 6. Subglobose, the anterior 

 side very short and gaping, hiatus with a marginated border ; thin 

 but firm, decussated, white and pellucid. 1. — Africa. 



A. Trapezoides. Lam 6. — E.t. 230. f. 6. — Osteodesma T. 

 Bit. 76. f. 8. Rounded-trapeziform, one side very short and 

 truncated, the other rounded ; slightly inequivalve, convex, thin, 



1 Mya Erodona, Lam. 3, is a Corbula. Mya Solemyalis belongs 

 to Osteodoma. 



