MANLIUS LIMESTONE OF HELDERBERG PLATEAU 51 
at Howe’s Cave.”* Mr. Hartnagel carefully examined these beds, 
failed to find gypsum, stated that the association is quite different 
from that of the pyrite layer (Salina) at Howe’s Cave, and concluded 
that it was more in harmony with known facts to refer these layers 
(Nos. 2 and 3) to the Rondout. 
The Manlius limestone is regarded as beginning with the base of 
No. 5 and extending at least to the top of No. 12, and perhaps a 
foot and a half higher, with a total thickness of 544+feet. This 
thickness is 84 feet greater than the sum of the Tentaculite and 
transitional beds as given in my paper of rgot, due to the addition of 
Nos. 11 and 12 of the above section which have a united thickness of 
about 9 feet. If to the 544+ feet which I have given as the thickness 
of the Manlius there be added the overlying transition layer of 
Harris, which he gives as 2 feet, then the thickness of the Manlius 
limestone will become 564+feet and the measurements of Harris 
and myself identical in the Indian Ladder cliff. 
The thickness of the Pentamerus limestone in the t9o01 paper 
was given as from 49 to 52 feet along the Indian Ladder cliff and 
subtracting the lower 9 feet, which is now put in the Manlius, there 
remains between 4o and 43 feet for the Coeymans limestone. 
It is also probably true that in the Countryman Hill section by Pros- 
ser and Rowe? a similar 9 feet ought to be taken from the base of the 
Pentamerus limestone and added to that of the Tentaculite to make 
the total thickness of the Manlius limestone, in accordance with 
the section of that hill given by Professor Harris.3 The writer has 
not been able to re-examine this section, but if the above change be 
made then the thickness of the Manlius limestone in the Prosser 
and Rowe section will become 55 feet and that of the Coeymans 
limestone, 41 feet. 
t Bull. Am. Pal. No. 19, p. 25. 
2 Seventeenth Ann. Rept. State Geol. [N. Y.], 1899 [1900], pp. 329-42. 
3 Bull. Am. Pal., No. 19, p. 26. 
