030 Systematic Paleoxtology — Upper Devonian 



Genus NUCULITES Conrad 

 NuCULITES sp. ? 



Description. — The presence of this genns in the Jennings of Maryland 

 is indicated by a single specimen too incomplete for identification yet 

 showing the hinge teeth and the anterior vertical interior ridge or clavicle 

 behind the forward muscular scar. 



Occurrence. — Jennings Formation, Chemung Member. West slope 

 of Polish Mountain ; Allegany County. 



Collection. — Maryland Geological Survey. 



Family LEDIDAE 



Genus PAL/EONEILO Hall 



Pal^oneilo constricta (Conrad) 



Plate LXI, Pigs. 7-10 



Nuculites constricta Conrad, 1S42, Jour. Acad. Nat. Sciences, Phila., vol. 



viii, p. 249, pi. xv, fig. 8. 

 Palwoneilo constricta Hall, 1885, Pal. of N. Y., vol. v, pt. i, p. 333, pi. xlviil, 



figs. 1-16, pi. li, fig. 17. 

 PalcEoneilo constricta Grabau and Shlmer, 1909, N. Amer. Index Foss., vol. 



i, p. 400, figs. 510o, b. 

 Palwoneilo constricta Cleland, 1911, Bull, xxi, Geol. Survey Wis., p. 102, 



pi. XX, figs. 9, 19-22. 



Description. — Shell of rather small size, ovate-cuneate, subnasute be- 

 hind. Basal margin rounded in the middle and anterior portions, straight 

 or slightly constricted toward the posterior end. Posterior end narrow 

 and constricted below. Valves equally convex. Beaks at anterior third. 

 TJmbonal ridge rounded with a depression or undefined furrow below it 

 extending from just behind the beak to the postinferior margin. 



Surface with fine, concentric, thread-like lines. Hinge with numerous 

 denticulations and sockets characteristic of the genus. 



Length 20 mm.; height 14 mm. 



Occurrence. — Jennings Formation, Chemung Member. Northeast 

 of Deer Park ; National Eoad on top of Green Eidge. Woodmont Mem- 

 bee, Ithaca Fauna. Woodmont, 710. 



Collection. — Marvland Geological Sun-ev. 



