(ot a Eh Be Sn ‘ ee eer Ng . x PAR sy et Gite 
256 .W. B. Dwight— Fossils of the Wappinger Valley. 
Mr. J. F. Whiteaves, I have been able to examine, differs in 
several points, as lack of curvature, less proportional size of 
siphuncle, different shape of cross-section, stronger forwa 
arching of the septa near the siphancle, and other features. 
Locality—Calciferous, Ledge D, Rochdale, N. Y. 
Cyrtoceras microscopicum, i. sp. 
Fig. 11 
Shell very small and with exceedingly thin, delicate walls. 
It is known only in the exhibition of a longitudinal section of 
a single specimen. It is much curved on the inner margin, 
and very moderately on the outer one; its taper is apparently 
very rapid, but as some of this appearance may be due to pos- 
sible obliquity of the section, no definite rate can be stated. 
Septa extremely delicate and crowded together at the rate of 
about 96 to the inch, with a gentle concavity, and meeting the 
dorsal and ventral margins at the same level. Neither the 
siphuncle nor the cross-section are known. The only specl 
men collected has a length of 6°5™™, while the transverse diam- 
eters at the extremities are respectively 5™™ an 
Locality—F, Calciferous, Rochdale, N. Y. 
Locality—Calciferous, Ledge D, Rochdale, N. Y. 
Orthoceras Henrietta n. sp. 
Figs. 13, 14 and 14a, 
one to ten, annulated, with generally from eight to ten Tl 
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