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NEW YORK STATE MUSEUM 



A small patch of the basal quartzite was found resting on the 

 granite gneiss at Fly mountain, evidently faulted with it. It was 

 also found reposing on a small inlier of these rocks outcropping 

 between the base of the Bald Hill spur and the southern extremity 

 of the Glenham gneiss belt, in the town of Matteawan. These 

 facts afford additional evidence of the age of the rocks of the 

 Glenham belt. 



Fishkill limestone. This belt of Cambro-Ordovicic limestone 

 as displayed within the quadrangle has yielded fossil evidence of 

 its age despite the mctamorphism it has undergone. In the Hook 

 district south of Johnsville, where the strata have been preserved 

 in more nearly their original relationship, I have found the scanty 

 but conclusive evidence of the age of the blue, compact limestone 

 overlying the hard, compact quartzite in the presence of well pre- 

 served opercula of H y o 1 i t h e 1 1 u s m i c a n s . In the town of 

 Fishkill, northwest of the road from Fishkill Milage to Matteawan, 

 between it and the Glenham gneiss belt, and extending a couple 

 of miles roughly paralled with the outcrop of the latter, I have 

 traced a belt of hard limestone weathering grayish white, but 

 showing buff-colored markings on fresh surfaces, with weathered 

 surfaces showing among the lichens the closely compacted whorls 

 of what I believe to be O p h i 1 e t a compacta Salter. The 

 belt can not be traced beyond the road from Fishkill Milage to 

 Wappingers Falls. Faults and metamorphism have greatly ob- 

 scured, if they have not obliterated it. In the limestone at Old 

 Hopewell, near the old furnace, and just north of Gregory's grist- 

 mill, I have found fragments of Orthoceras and one complete speci- 

 men, as yet unidentified, weathered out on the surfaces of a gray, 

 banded crystalline limestone, very close to marble in the degree 

 of metamorphism which it shows. 



We have evidence of the presence of the lowest Cambric and 

 the lowest Ordovicic in this limestone belt, by the discovery for the 

 first time, of actual fossils. In the final report other less certainly 

 defined but important details may more pertinently be discussed. 



Wappinger limestone (Barnegate limestone, Mather). In 

 this belt, first called the " Barnegate limestone," by Mather, but 

 because of the association which the Wappinger creek lias with 

 it for many miles, now more commonly called the " Wappinger 

 limestone," additional confirmatory discoveries have been made 

 which extend somewhat the boundaries of certain terranes within 



