Maryland Geological Survey 335 



Description. — Shell elongate, oval, length usually about two-thirds 

 the width. Cardinal lines nearly straight or slightly arcuate. Basal 

 margin regularly arcuate, anterior and posterior margins broadly 

 rounded. A nearly vertical clavicle extends from the hinge-line just 

 anterior to the beaks two-thirds the distance to the basal margin. Valves 

 moderately convex in the umbonal region, less convex in the lower and 

 posterior portions. Beaks anteriorly placed, appressed and not rising 

 above the hinge-line. Umbonal slope undefined and broadly rounded 

 blending with the depressed posterior border. Transverse teeth slightly 

 arched, with the crest toward the beak. Surface marked by fine con- 

 centric striae. Three specimens measure respectively 7, 8, and 8 mm. in 

 length, and 11, 14 and 13 mm. in height. This species is rather closely 

 allied to Nuculites oblongus from the Hamilton. It is distinguished from 

 this shell, however, by the greater proportional width, the broader, more 

 regularly rounded, posterior margin, and the less pronounced umbonal 

 slope. 



Occurrence. — Romney Formation, Onondaga Member. Williams 

 Road, 31^ miles southeast of Cumberland. 



Collection. — U. S. National Museum. 



[E. M. Kindle.] 



Family LEDIDAE 



Genus PALAEONEILO Hall 

 Palaeoneilo constricta (Conrad) 

 Plate XXVI, Figs. 9-12 



Nuculites constricta Conrad, 1842, Jour. Acad. Nat. Sci. Phila., vol. viii, p. 



249, pi. XV, fig. 8. 

 Nucula hellatula Hall, 1843, Geol. N. Y., pt. iv, p. 197, fig. 7 on p. 196. 

 Palaeoneilo constricta Hall, 1870, Prelim. Notice Lamellibranchiata 2, p. 7. 

 Palaeoneilo constricta Hall, 1885, Pal. N. Y., vol. v, pt. i, Lamellibranchiata ii, 



p. 333, pi. xlviii, figs. 1-16; pi. li, fig. 17. 

 Palaeoneilo constricta Clarke, 1903, N. Y. State Mus., Bull. 65, p. 474. 

 Palaeoneilo constricta Clarke, 1904, N. Y. State Mus., Mem. 6, pt. 2, p. 311, 



pi. XV, figs. 9-13. 

 Palaenoeilo constricta Grabau and Shimer, 1909, N. Am. Index Fossils, vol. i, 



p. 400, figs. 510a, b. 



