84 PALEONTOLOGY OF NEW JERSEY. 



Genus RANGIA Desinoulins. 



liANGIA (PER1SSODON) MINOR? 



Plate xv, figs. 4-6. 



Gnathodon minor Conrad: Am. Jour. Sci., vol. 41, 1st ser., p. 60, PI. n, fig. 14; 



Miocene Foss., p. 69, PL xxxix, fig. 6; Tuoiney and Holmes, Plioe. Foss. S. C, 



p. 99, PL xxiii, fig. 2. 

 Bangia minor Conrad : Proe. Acad. Nat. Sci. Phila., 1862, p. 573. 

 Bangia (Perissodon) minor (Conrad), Meek: Check List Miocene Foss., p. 11. 



" Subtriangular, convex-depressed, inequilateral; posterior extremity 

 truncated and nearly direct; umbonal slope angulated. 



"The hinge resembles that of M. [(?.] grayi. The shell is proportionally 

 shorter and less ventricose, and is distinguished by the more direct posterior 

 margin." (Conrad, in Miocene Fossils.) 



I have seen but a single valve (right) that 1 can refer to this species, 

 and I am in considerable doubt in regard to that one. The form of the 

 shell closely resembles Mr. Conrad's figure, both in outline and convexity, 

 as in size ; but as he has not figured the interior, and a& I have not seen the 

 type, I can only judge of its internal features by the statement that it 

 resembles Gnathodon Grayi in this respect, which it does only very distantly. 

 The specimen is of a triangular or triangularly ovate form, moderately con- 

 vex, umbonal angle distinct, and the slope abrupt. The posterior end is 

 slightly arcuate and the anterior rounded.. Surface smooth and semipolished. 

 In the interior the hinge has a single thin and almost sharp central tooth, 

 with a small pit on each side. On the anterior side a moderately well- 

 developed lateral tooth is distinctly shown, with two supplementary teeth, 

 and also a supplementary tooth on the posterior side. These are exceed- 

 ingly thin and small, and the doubling of the one on the anterior side may 

 be an accidental feature. The muscular imprints are small but distinct and 

 the pallial sinus is wide and shallow. The shell is not a true Mactra, neither 

 is it a true Rangia, but it differs too much from the hinge features of Con- 

 rad's type of Perissodon, Gnathodon Grayi (= G. clathrodonta), to render it 

 entirely safe to place it in that genus. So I have placed it under Rangia 

 provisionally. 



Locality: The specimen used is from Shiloh, N. J., and belongs to the 

 National Museum collection. 



