114 



NEW YORK STATE MUSEUM 



From the top of the Mix and O'Reilly quarry, transitional beds 

 from the Manlius to the Coeymans extend to the foot of the 

 Coeymans ledge which crops out in the wood behind the cemetery. 

 These beds are covered in the interval, but are well shown in The 

 quarry next south in the hillside, where the Coeymans is also 

 quarried for road metal. 



The total interval from the top of the Cobleskill to the base of 

 the transition beds is 59 feet, 6 inches. The transition beds which 

 may be classed with the Manlius, since they partake more of the 

 character of this rock than of the Coeymans, have a thickness of 

 12 feet and G inches, making a total for the Rondout and Manlius 

 limestones at Schoharie of 72 feet. This is somewhat less than 

 the measurement at Howes Cave, where the same formations 

 have a combined thickness of 91 feet. This appears to be due 

 to the more argillaceous character of the lower or Rondout beds 

 of the series at Howes Cave, though similar argillaceous beds are 

 found in the outcrops on West hill and presumably exist in the 

 covered portions of this formation in Schoharie. 



The fauna of the transition beds is very interesting, since it 

 represents oscillating conditions between the Manlius and the 

 Coeymans. They contain at intervals a pure fauna of S p i r i f e r 

 v a n u x e m i [fig. 24] and Tentaculites, or again beds with abun- 

 dant S t r o p h e o d o n t a v a r i s t r i a t a [rig. 23] . and others 

 with a variety of C a m a r o t o e c h i a semiplicata [fig. 

 27], with a very angular anterior portion, and other typical Hel- 

 derbergian species. 



The number of fossils characterizing the Rondout and Manlius 

 in this region is not very great. Some of the corals and brachio- 

 pods of the Cobleskill extend upward into the Rondout and some 

 even reappear in the Manlius limestone. Among these are Favo- 

 sites h elder bergi a v var. precedens, S t r o m a - 

 topor a cf. a n t i q u a , C a m a r o t o e <• h i a 1 a m e 1 1 a t a 

 [fig. 13] S pi r i I e r eriensis [fig. 1 1 ] and S . c o r a 1 1 i n - 

 ensis [fig. 10], There are no Stromatopora beds in the Man- 

 lius of this region as there are in tin 1 Hudson valley.- At 



