695 



Plat. 



from Oollett's Indiana, 1881, p. 318, pi. 29, figs. 1-12 (omittingfi^. 

 11). Also plate 30, figs. 1-15. — In Pennsylvania collected by 

 0. E. Hall, 1875, in Furgason and Aughwick valleys, Hunting- 

 don Co., in Clinton shales (133' thick) overlying the Clinton 

 fossil ore led at Orbisonia, and McKeesburg (T3, p. 141). See 

 Cat. 00, p. 233, specimens 505-14, 505-25, at McKee'sore bank. 

 Note. The Platyostoma ? of H. D. Rogers, Geology of Pa. 



VI ^^..rrrr.. ^^^^'> P^S® ^^^^ ^g" ^^^7, from tho Augh- 



wick valley, is probably the same; 

 but is assigned by him to the Lower 

 Helderlerg limestone as he did not 

 recognize the existence of the Niagara 

 formation in Middle Pennsylvania. — 



latystoma plebium, Hall. 



From Collett's Indiana Re- 

 port of 1881, page 319, plate 

 29, fig. 14, 15, opposite sides 

 of a specimen, showing height 

 of spire and form of volution 

 and aperture. — Niagara^ VI. 



Platystoma ? subangulatum. Hall, Pal. N. Y. Vol. 3, 



W ..^1^ ^"^ ^^ ..ii^^fc^ -^ 1859, page 301, plate 55, figs. 



3 <z, side, 3 5, base, of speci- 

 men without shell, there- 

 fore genus doubtful; from 

 the red compact layers of 

 the Lower Llelderhergy in 

 Albany Co., N. Y., F/.— Spec. 792-7, Orbisonia, Pa., from 

 Oriskany lime sand.^ resembles closely figure in Hall. — VLl, 



Platystoma (?iiagarensis^ Var.) trigonostoma, Meek. 

 Proc. Acad. Nat. Sci. Phila. 1871, Niagara, — Pal. Ohio, Vol. 1, 

 1873, page 185, plate 16, figs. 3, a, J, upper and under side of 

 cast; G^ upper side of another specimen. Mr. Meek makes this 

 a variety of Hall's jP. niagarensis. Pal. N. Y. II, pi. 60; Hall 

 & Whitfield, List, Louisville, 1872. See woodcut on Pal. Ohio, 

 I, p. 186. Niagara, Yellow Springs, 0. — Vh. 



17 



