142 W. B. Dwight — Recent Explorations in the 



Besides the strata already mentioned, there are limestones 

 filling the eastern side of the valley east of the mountain, 

 cropping out in Thomas's quarry on the northeastern edge of 

 Pine Plains village, forming Mill Hill on its eastern edge, and 

 other. hills easterly as far as Bethel, and (in conjunction per- 

 haps with the quartzite-limestone Olenellus belt,) passing north 

 into Columbia County ; also forming a belt about six miles long, 

 and from a quarter of a mile to a mile wide in the Shekomeko 

 valley, from Pnlver's Corners on the north, to " The Square," 

 two miles south of Shekomeko Station ; also a very irregular 

 strip about one mile and three quarters long and from a quar- 

 ter of a mile to a mile in width, north of Bangall. All these 

 outcrops I have searched and studied in detail, and have found 

 them to be Cambro-Ordovician strata, much faulted against 

 each other, and against the Hudson River Shales, especially in 

 the Bangall strip. ]STo Trenton outcrops have been found. 

 Fossiliferous Calciferous strata occur at Attlebury Station, near 

 the Moravian monument, at Bethel, and quite extensively at 

 and south of Shekomeko. 



The greater part of these limestones are Cambrian in ap- 

 pearance, passing very frequently into the calcareous shales 

 characteristic of that zone in this county. But no fossils 

 except those of the Calciferous strata have been found in any 

 of the belts just named with the exception of a single frag- 

 ment. This was found at the base of Mill Hill in Pine Plains 

 Tillage, and may be either a Kutorgina or a Lingulepis. It is 

 therefore at present impossible to determine the eastern edge 

 of the Olenellus strata in the neighborhood of Pine Plains, or 

 to distinguish, in this vicinity, the higher Cambrian strata, ex- 

 cept in the single instance which will now be mentioned. It 

 can scarcely be doubted, however, that the Potsdam zone is 

 largely represented in connection with the Calciferous. The 

 deep cutting on the railroad just north of Husted station is 

 most probably in the Potsdam. 



In July, 1887 the search in the limestones and calcareous 

 shales immediately overlying the Olenellus limestone at the 

 south end of Stissing Mountain was rewarded by the discovery 

 of two or three fossils. No fossiliferous layer was then found ; 

 the organisms obtained were referred to the Potsdam zone 

 which was to be expected in that position. It was not until 

 the summer of 1888 that, by the discovery of a fossiliferous 

 layer at this spot, the true significance of these important or- 

 ganisms began to appear. 



The locality is in the first rock-cutting on the New York 

 and Massachusetts Railroad, a little less than half a mile south 

 of Stissing station. The organisms have been found chiefly in 

 a thin layer of limestone and calcareous shales close to the 



