90 PALEONTOLOGY OF NEW JERSEY. 
shorter and not quite so attenuate, while the umbos are larger and more 
rounded and prominent. The anterior end of the shell is so little gaping 
that it can hardly be said to be a feature, at least when examining the sep- 
arated valves it is scarcely apparent; but the posterior side is very distinctly 
so. The greatest difference which I have noticed between Mr. Wagner's 
description and the features of the New Jersey shells lies in the great promi- 
nence of the teeth in the latter, whereas he says they are not prominent in 
his specimen. Still I do not think this of much importance, but only prob- 
ably an individual difference. The resemblance to P. reflera Say is too 
slight to need comparison here. The other nearest approach to this one is 
seen in P. porrecta Conrad (Miocene Fossils, p. 71, Pl. xu1, fig. 2), but here the 
posterior end is still more elongate and narrowed, and the teeth more slender 
and smaller. Still I think it probable they may be only variations of the one 
species. In the interior of this shell the sinus is very large and much deeper 
than in P. refleca or P. Americana, but the line is not broken into dots or 
patches, as is required in the genus Glycimeris of Klein, consequently I 
retain it under Panopzea. 
Formation and locality: Inthe gray marly beds of the Miocene at Jericho, 
N. J. From the collection of the National Museum. 
Genus SAXICAVA Bellevue. 
SAXICAVA MY 4FORMIS. 
Plate xvi, figs. 4 and 5. 
Saxicava myeformis Conrad: Proc. Acad. Nat. Sci. Phila., 1862, p. 585; Meek, Check 
List Miocene Foss., p. 12. 
Thracia myeformis Conrad: Am. Jour. Couch., vol. 2, p. 70, Pl. Iv, fig. 3. 
Thracia myeformis Heilprin: Tert. Geol. U.S., p.8; Miocene Mollusca of New Jersey, 
Proc. Acad. Nat. Sci. Phila., 1887, pp. 397 and 403. 
“Ovate, thin and fragile, inequilateral; extremities rounded; surface 
marked with fine rugose concentric lines; cardinal teeth small, two in the 
right valve.” (Conrad in Proc. Acad. Nat. Sei., Phila., 1862, p. 585.) In 
the American Journal of Conchology, loe. cit., Mr. Conrad describes the 
same shell as follows: ‘‘ Ovate, inequilateral; posterior side somewhat pro- 
