Plat. 



676 



in 000, 1888, specimen 200-6 (two), was found at Mapleton, 

 Huntingdon Co. glass sand quarries of Orishany. VIL 



Platyceras platy stoma, Var. alveatum, Hall, Pal. N. Y. 

 Ill, 1859. Lower Held. VL 

 Platyceras plicatile, Hall, III. Z. Held. VL 

 Platyceras plicatum, Hall. Pal. N. Y. Vol. 3, 1859, p. 334, 







HalL 



pl. 64, fig. 1, a young specimen in which the plications have 

 not yet been developed; fig. 5, a large specimen widened un- 

 naturally by pressure ; from the Delthyris shaley limestone of 

 the Lower Helderierg. VL, — In Pennsylvania, collection by 

 C. E. Hall, spec. 703-14 (two) from Royer's ridge, north of 

 the road -crossing at Orbisonia, Huntingdon Co. (00, 1875), 

 Oriskany. Also Olaypole's catalogue (in 000) names as a 

 variety P. planum., specimen 200-10, from the glass sand quar- 

 ries of Mapleton, Huntingdon Co. Orishany, VLL, 



Platyceras primaevum, Billings (1881, Can. Nat. VI, 220) 

 ^'^ ilAI Walcott, Bulletin No. 30, U. S. G. 

 8. page 130, plate 12, fig. 5 cast, 

 right side ; 5 a left side, enlarged 

 to show characters of outside sur- 



_7 _ I face of shell. Lower Cambrian 



conglomerate linestone at Troy, and below Quebec. Z. G, 



Platyceras primordiale, Hall, 16th Rt. N. Y. 1863, Pots- 

 dam sandstone. L. 



P. proclive., Ring. ; pyramidatum., Hall ; quincyense^ Mc- 

 Ohes. ; quinquesinuatum., Ulrich. (S. A. M.) 



