REPORT OP THE STATE PALEONTOLOGIST 1902 1147 



gives it about the same thickness that it has at Rondout. The 

 10 foot bed of cement rock above is the Salina waterlime, while 

 the dark colored rock containing corals represents the Cobleskill. 

 Regarding this " Stromatopora layer " as Manlius, it would allow 

 but 10 feet between the Wilbur limestone and the Manlius or what 

 amounts to the same, 10 feet for the combined thickness of the 

 Salina waterlime, the Cobleskill limestone and the Rondout 

 waterlime. 



The interpretation of this section as given by Darton seems to 

 have had much to do with his ascribing certain features to the 

 Manlius or " Tentaculite " limestone which in reality do not 

 exist, and, since his paper is one that is often quoted, it may not 

 be altogether out of place to call attention to this matter. In 

 describing the Manlius limestone in Ulster county, Darton 1 says : 

 "There is included at or near its base, notably in the quarries near 

 Rondout, a dark gray, impure limestone containing many corals 

 and representing the Stromatopora horizon." This bed is un- 

 questionably the Cobleskill, the real Stromatopora horizon being 

 much higher. Its position is indicated in the section at Rondout. 

 Again, in his description of the Manlius in Albany county, he 

 says: 2 "Toward the base of the series there is usually a more 

 massive bed containing Stromatopora, but the member is not con- 

 spicuous in Albany county in its typical development." It is very 

 evident that Hall did not know what Darton meant by the 

 Stromatopora bed above alluded to, for, following the last quota- 

 tion, Hall adds as a correction the following footnote: 



This Stromatopora bed is excellently exposed on the Albany 

 and Schoharie plank road beyond Altamont; also about 2 miles 

 west of the road from Albany to Clarksville on the land of Mr 

 Merkel on the same road 2 miles northeast of Clarksville . 

 Most of these exposures show that the bed lies but a few feet 

 below the Pentamerus [=Coeymans] limestone. 



The Stromatopora bed as thus located by Hall was also noticed 

 by Darton, but the locality is not given in his description; he 

 says : 



In the upper members there is a thin subbedding, indicated by a 

 ribboning of alternating lighter and darker tints, constituting 



1 N. Y. State Mus. 47th An. Rep't. 1894. p.449. 

 a N. Y. State Mus. 47th An. Rep't. 1894. p.441. 



