476 Systematic Paleontology 



Platyceras tenuiliratum Hall? 

 Plate LXXXV, Figs. 1, 2 



Platyceras tenuiliratum Hall, 1859, Nat. Hist. N. Y., Pal., vol. iii, p. 317, pi. 

 Iviii, figs. 1-5; and pi. lix, figs. 6a, 6, 1861. 



Description. — " Shell small, depressed, siibovoid or subdiscoid, with the 

 last volution very ventricose. Spire slightly raised above the plane of the 

 outer volution : volutions about three, the first and second very minute, 

 and the last one rapidly expanding; aperture campanulate, vpith the lip 

 broadly reflexed on the posterior and part of the right side. Surface 

 marked by fine thread-like striae, which often become lamellose on the last 

 volution, and these are cancellated by very fine revolving striae." Hall, 

 1859. 



Occurrence. — Heldeeberg Formation, Keyser ? Member. Cash 

 Valley. 



CoUeciion. — U. S. jSTational Museum. 



[Maynard.] 



Platyceras axgulare n. sp. 



Plate LXXXV, Fig. 3 



Platyceras angulare Rowe, 1900, MSS. 



Description. — " Shell depressed, subconical, sides sloping gradually 

 toward the aperture; whorls about one; aperture and apex not known. 

 Surface marked by five or six strong angular longitudinal ridges running 

 from the apex to the aperture. Upon these ridges are oblong nodes. 

 Where the shell is not exfoliated fine concentric striag transverse the shell 

 at right angles to the ridges. The general shape together with the sharp 

 angular ridges separated by broad shallow sinuses distinguish this species 

 from all others. 



" Dimensions : Width 3 cm. ; height 3.7 cm." Eowe, 1900. 



Occurrence. — Oriskany Formation, Eidgely Member. Warren 

 Point, Pennsylvania. 



Collections. — Maryland Geological Survey, New York State Museum 

 (fide Eowe). 



[Eowe.] 



