72 PALEONTOLOGY OF NEW JERSEY. 



Venus (Artena) st amine a- 



Plate xiii, Figs. 3-10. 



Cytherea staminea Conrad; Miocene Foss., PI. xxi, tig* 1; Am. Jour. Conch., vol. 6, 



p. 76. 

 Dione (Cytherea) staminea Conrad ; Proc. Acad. Nat. Sci. Phil., 1862, p. 575. 

 Dione staminea (Conrad) ; Meek Cheek List, Miocene Foss., p. 10. 

 f Venus latilirata (Con.) Heilprin; Proc. Acad. Nat. Sci. Phil., 1887, p. 403. 



The only description given of the species by Mr. Conrad which I have 

 been able to find is that in vol. 6, p. 76, of the Am. Jour. Conch., where he 

 says: "The species is triangular, very ventricose, slightly contracted poste- 

 riorly, and between the ribs are close, minute, rugose, concentric lines [;] 

 umbonal slope terminal, angular; posterior slope depressed, lunule cordate.'' 



Two single valves of small size are all that represent this species 

 among the collections from New Jersey. These are triangular in outline, 

 with deep valves, and the surface is marked with three and four strong, con- 

 centric, recurved, lamellar folds, and the shells are less than half an inch 

 in their greatest diameter. A large entire individual from South Caro- 

 lina, however, serves to give the true adult features. This shell is triangu- 

 larly circular in outline and very ventricose; the beaks are rather small 

 and somewhat appressed, but strongly incurved, directed forward, and 

 placed in advance of the median line ; base of the shell very gibbous with 

 a strong constriction just in front of the umbonal margin; anterior end 

 rounded and the posterior umbonal margin strongly arched; lunule large, 

 deeply marked, and broadly cordate ; posterior slope incurved and depressed 

 below the umbonal margin; posterior end slightly produced.' Disk of the 

 valve ventricose, with a* strongly marked sulcus just anterior to the umbonal 

 margin. Surface marked by distant, strongly elevated, lamellose, concen- 

 tric ribs and by very fine rugose lines between. Shell substance thick. 

 In the interior the hinge plate is broad with strong teeth separated by deep 

 pits; muscular scars distinct and the pallia! sinus small and angular; mar- 

 gins of the valve finely crenulated. 



The specimen from which this description is taken is more fully grown 

 than that figured by Mr. Conrad in his Miocene fossils, and shows the pos- 

 terior sulcus, just in front of the terminal umbonal ridge very decidedly. 



