ENPages
p. 6
Platyceras Gebhardii, Conrad, N.York Geol. Rep. 1840 p 206
Differs from P. ventricosum in having a much larger spire which is longitudinally carinated, near the apex and with distinct transverse undulated striae.
p. 7
Upper Silurian -
Cattskill Shaly Limestone
Schoharie N.Y.
p. 8
Gasterop
(Platyceras of Conrad)
Acroculia Niagarensis, Hall, Pal. of N.Y. vol. 2 p. 288 pl. 60 fig. 3
Apex involute, scarcely forming a volution, gradually expanding below with two or three longitudinaly folds or undulations, transversely striated; striae undulating across the elevations and depressions of the sur= face. - Shell rounded, with gentle longitudinal elevations undulations, which do not rise into a ridge or angle.
L. 1.5
p. 10
Gasteropoda
Acroculia angulata, Hall, Pal. of N.Y. Vol. 2 p. 289 pl. 60 fig. 4.
Apex attenuated, involute, form= ing one or two minute volutions, below which the shell extends in a broad curve, expanding rapidly towards the aperture which is much dilated; surface angulated, a sharp carina on the up= per and lower outer margin of the volution an obtuse carina on the middle of the back, and the inner margins angulated; transverse section unequally pentan = gular; surface finely striated; strioe undu= lating over the surface, arching upwards on the sides, and downward or towards the aperture between the outer angles and the central carina, upon which they are twice undulated or bent.
L. 0.8
