1034 NEW YORK STATE MUSEUM - 



dents in the Summer School of Geology in Columbia University. 

 Nearly all the collections of fossils which have served as the 

 basis of the accompanying fauna! lists, were made by the uni- 

 versity parties under the direction of the instructors. The col- 

 lection, however, on which the list of Port Ewen fossils is based 

 was made by myself, that I might be certain of the range of the 

 species. A general map was prepared by the field parties, which 

 afterward served me as a further basis for detailed study. 



I wish here to express my indebtedness to Prof. John C. 

 Smock, who not only furnished us with the accurate topographic 

 base map, but also rendered other assistance during the progress 

 of the field work. 



STRATA OF THE BECRAPT REGION 



The following formations are exposed at Becraft mountain. 

 The thicknesses appended are the best estimates, whenever 

 actual measurement was not possible. 



Feet 



11 Onondaga limestone 20-25 



10 Schoharie grit 200 



9 Esopus grit : 100 



j 8 Oriskany quartzite 1-2 



7 Port Ewen (Kingston) limestone 25 



6 Becraft limestone 40-45 



5 New Scotland shaly limestone 70-75 



4 Coeymans limestone. . . ." 42-45 



Siluric 3 Manlius limestone 55 



Cham- j 2 Hudson river slates 



plainic ( 1 Burden conglomerate 



1 BURDEN CONGLOMERATE 



This name is proposed for a calcareous conglomerate in which 

 the pebbles are chiefly limestone embedded in a silicious sand, 

 which in turn is held together by a more or less calcareous 

 cement. The limestone of the pebbles is in part a gray, compact 

 rock (calcilutite 1 ) not unlike the Manlius limestone and in part 

 a more granular mass (calcarenite (Grabau)). The matrix is 



'Grabau. Science Feb. 20, 1903. p. 297. Also Geol. Soc. Am. Bui. v. 14; 

 Paleozoic Coral Reefs, with notes on the classification of limestones. 



