GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 



135 



The lower beds of the Coeymans formation are generally massive 

 limestones, while the npper ones are more thin bedded and gener- 

 ally show a transition to the overlying New Scotland formation. 

 This relative character is maintained throughout the Helderberg 

 region, and is also found in the outliers east of the Hudson, 

 Mt Becraft and Mt Bob. Topographically this is expressed by 

 a cliff wherever the massive 





/ 



beds are exposed and by a 

 slope above this, formed by 

 the thinner bedded strata. 

 The cliff of the lower Coey- 

 mans is conspicuous every- 

 where in this region, being 

 particularly prominent on 

 both sides of West moun- 

 tain and on the south face 

 of Barton hill along the Fox 

 kill. The cliff not infre- 

 quently overhangs owing to 

 the recession, by weather- 

 ing, of the transition layers 

 between it and the Man- 

 lius. Thus there is generally 

 a cavernous recession at 

 the base of the Coeymans, 

 which in many places forms an adequate rock shelter [see 

 pi. 11]. It is at the base of this rock that the remarkable 

 crinoid M e 1 o c r i n u s p a c h y d a c t y 1 u s [fig. 33] has been 

 found, the locality furnishing most of the si3ecimens obtained, 

 being the cliff east of Schoharie courthouse. The thickness of 

 the formation at Kondoutj New Salem and at Indian Ladder is 

 the same as at Schoharie, i. e. 50 feet, while at Mt Becraft its 

 thickness is 45 feet. There is generally much chert in the upper 

 portion of this formation, but this appears to be wanting entirely 

 in the exposures of the Schoharie region. At Howes Cave the 



Fig. 33 Melocrinus i)ach y dacty lu s 



