194 PERMIAN FOSSILS. 



Family Astartidjs, King. 



CRASsiNiDiE,! J. E. Gray. 



I quite agree with Mr. Gray in making the genus Astarte typical of a distinct family 

 group. The dental and muscular systems, thick epidermis, and some other characters, 

 widely remove it from all those families in which Lamarck, Blainville, and other 

 conchologists have placed it. Jstartidce agrees with Trigoniidce only in being without a 

 siphonal inflexion. 



Genus Astarte, J. Sowerby. 

 Crassina, Lamarck. 



Diagnosis. — " Suborbicular or transverse: subinequilateral : hinge with two di- 

 verging teeth : a depression before the beaks : impression of the cloak entire, exhibiting 

 no siphon-cicatrix." (J. Sowerby.)^ 



As this genus, which contains several recent forms, was originally founded on a 

 fossil species, and consequently not so fully described as could be wished, it has been 

 considered necessary to add the description of it by Forbes and Hanley, the latest 

 writers on the subject. 



" Shell oblong, suborbicular or triangular, solid, equivalve, more or less inequi- 

 lateral, sometimes nearly equilateral, closed ; surface smooth, or transversely furrowed, 

 and covered by a conspicuous epidermis. Muscular impressions ovate, strongly 

 marked ; pallial impression simple, rather distant from the margin. Hinge composed 

 of two strong diverging primary teeth in one valve, and a primary tooth with a less 

 supplementary one, which is sometimes obsolete, in the other. Ligament external, 

 elongated, usually lodged in a lozenge. Lunule almost always distinct."^ 



It is suspected that the following species are the earliest created forms known. 



Astarte Vallisneriana, Kinc/. Plate XVI, fig. 1. 



Astarte (?), J. de C. Sowerby. Sedgwick, Trans. Geol. Soc. Lond., 2d series, 



vol.iii, p. 119, 1829. 



— (?) „ De la Beche, Geol. Man., p. 385, 1831 ; Germ. 



Transl., p. 459, 1832; 3d Eng. ed., p. 573, 

 1833. 



— Vallisneriana, King. Catalogue, p. 11, 1848. 



1 The epithet Crassinidce having no generic typical name, in consequence of the general abandonment 

 of Lamarck's Crassina, I have made free to substitute for it that of Astartidce. 



2 Mineral Conchology, vol. ii, p. 85. 



3 A History of British MoUusca, vol. i, pp. 450-1. 



