36 PALEONTOLOGY OF NEW JERSEY. 



0. canaliculata the denticulations are almost obsolete; while one given in 

 Goldf. Petraf., p. 10, PL LXXIV, Fig. 2, as 0. lunata Nils., is a very good 

 representative of the var. nasuta Morton. 



Formation and locality. — The species is common at many of the marl 

 pits in the Lower, Middle, and Upper Green Sands throughout the State, 

 as well as in many of the Southern States in the Eocene sands and clays. 



Genus GRYPH^A Lam. 



Gryphsea vesicularis Lam. ?. 



Plate III, Figs. 15 and 16 j Plate IV, Figs. 1-3, and PI. v. 



Ostrea vesicularis Lam. (1806). Ann. Mus., VIII, p. 160, PI. XXII, Fig. 3. An. sans 



Vert., Vol. 6, p. 209. 

 0. convexa Say. 1820, Am. Jour. Sci. and Arts., Vol. II, p. 42. 

 Gryphcea convexa Mort. Jour. A. N. S., Phil., Vol. VI, PL IV, Figs. 1 and 2, PI. V, Figs. 



1-3. Organic Eem., p. 53, PI. IV, Figs. 1 and 2. 

 G. mutahilis Mort. J. A. K S.', Phil., Vol. VI, PI. IV, Fig. 3. Synopsis, p. 53, 



PI. IV, Fig. 3. 

 Pycnodonta vesicularis (Fischer) Conrad. J. A. N. S., Phil., Vol. IV, p. 275, 1860. 

 Gryphcea vesicularis var. aucella Eoemer; Kried. von Texas, p. 74, PI. IX, Fig. 4. 

 Comp. G, digitata var. Tucumcarii (Sow.) Marcou; Geol. U. Am., p. 43, PI. IV, Figs. 1 a, 



&, and 2 and 3. 

 Comp. G. Fitcheri (Con.). U. S. and Mex. Bound. Surv., p. 155, PI. XXI, Fig. 3 a^e. 

 Comp. G. Fitcheri var. navia, See Mex. Bound. Surv., Vol. I, p. 155. 



Shell varying from depressed convex to highly gibbous on the lower 

 valve, and from flat to deeply concave on the upper valve. Outline varying 

 from subcircular with a very short cardinal line to semicircular, where the car- 

 dinal line is of considerable length ; the relative proportions of length and 

 breadth being equally variable, sometimes wider than long and again nearly 

 twice as long as wide. Left side, when looking on the flat valv6, more or 

 less lobed, often projecting in an extended finger-like anal tube a little 

 below the line of the hinge. Exterior of the shell strongly lamellose, and 

 most distinctly so on the convex side, which often shows strongly projecting 

 concentric lamellae having free edgjes ; apex of the lower valve often pre- 

 senting a broad cicatrix of attachment, while many specimens are found 

 which are entirely destitute of any such feature. Upper or flat valve 

 strongly lamellose, especially near the margin of old or thickened shells, 

 and the surfkce usually marked by strong radiating depressed lines, very 



