JURASSIC FOSSILS. 47 



FAMILY PTERIIML 



Genus INOCERAMUS, Sowerby, 1814. 

 Inoceramus? obliquus, Meek. 



PI. 7, Fig. 2, and 2 a. 



Shell small, (right valve) much compressed, obliquely sub- 

 ovate, sub-mytiliform ; beak attenuate, oblique and nearly or 

 quite terminal ; anterior side a little sinuous, and sloping back- 

 wards above, sloping and a little convex in outline below ; pos- 

 tero-basal margin narrowly rounded; posterior margin nearly 

 straight, ascending forward so as to intersect the short hinge at 

 a very obtuse angle. Surface apparently nearly smooth, or with 

 slight tracings of concentric markings, 



Length from the point to the beak, obliquely to the posterior 

 inferior margin, 1.14 inch; anteroposterior diameter, 0.68 inch; 

 convexity of left valve, 0.07 inch. 



Knowing nothing of the hinge of this little shell, nor of the nature of its left 

 valve, it is with considerable doubt I have ventured to refer it provisionally to 

 the genus Inoceramus. If it belongs to that group, it would fall into the section 

 Mijtiloides of Brongniart, unless the other valve is much more gibbous. 



Inoceramus ? rectangulus, Meek. 



PI. 7, Fig. 1, and 1 a. 



Shell (right valve) oval-oblong, higher than wide, much com- 

 pressed, anterior side straight, and almost vertically truncate 

 above, rounding into the rounded base below; posterior side 

 forming a broad semi-elliptic curve, rounding to the hinge above; 

 hinge short, and ranging very nearly at right angles to the trun- 

 cated anterior margin; beak placed directly over the anterior 

 edge, not prominent, or projecting above the hinge-line. Surface 

 with small, obscure, concentric wrinkles. 



