Chemung and Catskill.—Sterenson. 19 
5, Shales with second sand 260" 
6. [Allegrippus]| third oil-sand 30! 
7. Lower Chemung 320 | 
8. Girard 225’ 
9. Portage * 475! 1477" 
Prof. White placed the whole section to the base of the Cusse- 
wago in the Pocono or Lower Carboniferous, though seemingly 
with some hesitation respecting the lower members. ‘The Corry 
sandstone appears to be the representative of the Berea of Ohio. 
The Riceville shales are equivalent to the red rock of Butler and 
Venango as well as to the Montrose red shales of the eastern 
sections. Typical Chemung forms occur here at many places up 
to within 15 feet of the Cussewago sandstone. The Lachkawaxen 
isseldom coarse in northwestern Pennsylvania. The A/legrippus, or 
third oil-sand, is the persistent stratum in this region and the one 
possessing economic importance. Prof. White gives good reason 
for identifying it with the Panama conglomerate of New York. 
Prof. White found the same section in Warren county at Tidioute, 
twelve miles east from the Crawford line, and he regards the 
Coccosteus bed at Warren as the same with the Luchawaxen, or 
first Venango oil-sand. Mr. Carll’s section at Great Bend,* on 
the eastern edge of Warren county is of interest as showing the 
appearance of the ‘Catskill type,t as he terms it, there being 
above the Riceville shales, 88 feet of greenish gray sandstone 
with olive and red shales; so that somewhere between Tidioute 
and Great Bend the typically Catskill characteristics appear in 
the upper part of the section. Chemung fossils are found in the 
Riceville shales or Montrose Red shales and Sangu/nolites occurs 
in the Lackawacen. 
Meanwhile a noteworthy change has occurred below the Lacka- 
wacen, for though 327 feet of rock are shown, yet the A//egrippus 
or third sand is not reached; so that we are prepared for the con- 
dition shown by Mr. Ashburner’s generalized section of McKean 
county, next east’ to Warren along the northern border of the 
state. There we findt 
Pocono 250' 
Catskill 250° 
Chemung 1990' 
*Loc. cit. p. 641. 
tGeological Report on Warren county, J. Hf. Carll, Harrisburg, 1883, 
p. 302. 
tGeology of McKean County, Ete. C. A. Ashburner, Harrisburg, 
1880, p. 43. 
