REPORT OF THE STATE PALEONTOLOGIST 1902 1055 



material. On the whole, the rock may be considered an argil- 

 laceous calcarenite. 1 



The rock is readily distinguished from the Becraft limestone 

 by its texture and color, but not so readily from the Port Ewen. 



The total thickness of the Coeymans is about 45 feet. The 

 lower 20 or 25 of these are generally massive bedded, often 

 crinoidal, and form commonly a vertical cliff in conjunction 

 with the underlying Manlius limestone. The upper portion of 

 the Coeymans is thinner bedded, with more or less shaly layers 

 separating the beds, and this is expressed in the topography by 

 a sloping bank, with occasional low, reeflike rock ridges mark- 

 ing the strike of the strata. This feature is most readily 

 observed on the west side of the mountain, at the top of the 

 cliff facing the Ancram road between Jonesburg and fault 21. 

 The fossils are most abundant in this upper shaly portion, and 

 to some degree these beds form a transition to the New Scot- 

 land above. Atrypa reticularis is everywhere com- 

 mon, while Gypidula galeata is also frequent in these 

 beds. With these in the upper layers occurs rarely Spirifer 

 macropleurus, showing the beginning of the New Scot- 

 land fauna. 



The following is a list of the fossils of the Coeymans lime- 

 stone of Becraft mountain, obtained chiefly from the upper 

 beds. 



1 Monotrypa tabulata (Hall). Not very common. 



2 Favosites helderbergiae Hall. Several speci- 

 mens were found in the top beds of this limestone. Some speci- 

 mens were also found in the lowest beds. 



3 Enter olasma strictum (Hall) . Not uncommon 

 in the upper beds. 



4 Fistulipora torta Hall. Abundant. 



5 Roemerella grandis (Hall). A specimen having 

 the size and form of this species. The surface is covered with 

 very irregular concentric striae, and extremely fine radiating 

 lines are visible only between the concentric striae. 



' Grabau. Science, n. ser. Feb. 20. 1903. p. 297. 



