Plat. 



692 



Platystoma hemisphericum, {Eaomphalus hemispher 



Hall. 

 39 J. 



icus)^ Hall, Geology of the 

 Fourth District, N. Y. 1843, p. 

 109, figs. 39, 1,15, Niagara lime- 

 stone, Vb. — Note. The spelling Platyostoma so frequently 

 employed, if in accordance with the old rule that compounds 

 should be made with the Greek genitive and not with the 

 nominative, is nevertheless wrong, as it should be Plateostoma. 

 But the accepted spelling Platyceras, Flatycrinus^ etc. justifies 

 the use of Platystoma, ^' wide mouth.'' 



Platystoma lineatum, Conrad, ( Platystoma lineata ? 

 V/// 



F/5.20. 



Conrad, Jour. Acad. N. S. Phila. Vol. 8, p. 275, pi. 17, f. 7.) 

 Hall's 15th Report, 1862, p. 40, pi. 5, figs. 19, 20, drawn from 

 one of two hundred individuals found in the Hamilton. Well 

 preserved surfaces are beautifully cancellated, and some remains 

 of these markings may be seen even in worn and partially peeled 

 specimens. Looks something like P. turhinata ( VII 5, Villa) 

 but the spire is ne\ 3r so depressed, etc. A cast from Batavia 

 is 3 inches long, with a vertical diameter of aperture only 1^ 

 inches. Found the whole length of New York in the Tipper 

 Helderhurg ; and in the Hamilton of Western New York. — 

 Vila. VIII G. 



