J. D. Dana—Hudson River Age of the Taconic Schists. 381 
same reason, at pes sis a time (March 21), and I a left 
the region to be reported on further by Professor Dwig 
Another locality af. fossils in the Wappinger Valley limestone 
at nuvi four miles east of crete sie, had bee 
tion to join me in the excursion—-and it is not less prolific. 
Great surfaces are covered with the Crinoidal remains, and all 
inches wide at its larger end, and remains of large specimens of 
Receptaculites. I refer to the article ee this for Professor 
Dwight’s preliminary account of t 
Previously, early in December file ps tine the first snow- 
storm of the late snowy winter), I made a search for fossils at 
the northern end of the Wappinger Valley limestone, in eastern 
Ancram, just west of the extremity of Winchell’s Mountain 
and not three miles distant from the Taconic Mountains, and 
found what I then and now believe to be the common Trenton 
species, Orthis occidentalis ;* and with it there is another kind, 
d thickness 
indicated in the accompanying figure. The thin shell is con- 
verted into white calcite (through the espaol sm) ex- 
cepting in some parts an extremely thin exterior layer; and 
over a portion of the exterior (at c) 
there are sections of a few of the 
“igus The hinge side of the shell 
wanting in the specimen. 
Sige section made through 
the more convex (or ventral) valve 
was found to have the form which 
it should have if of the species here ; 
supposed ; and so for the other alee: The evidence is therefore 
ae strong in favor of its being this common Trenton Brachi- 
1. 
ec 
The forms referred doubtingly to Strophomena allernata 
have the arcuated outline, shape and thickness, that would 
belong to sections of this arcuate shell. They are of white cal- 
cite and correspond to individuals one to two inches broad and 
diminishing mostly from a fourth to a sixteenth of an inch in 
thickness. Besides the sections, there are ae broad concave 
surfaces like the inner surface of valves. ppearance 0: 
Striation can be detected in connection with oa of the forms. 
* The specimens were from a large freshly broken = of limestone by the 
road side that was evidently derived froin an outcrop near by. 
