PRossER.|  Cretaceous.—Comanche Series of Kansas. 1638 
ish sandstones and arenaceous shales belong to the Dakota (?). The 
cafion is about fourteen miles northwest of Ashland, probably on 
section 36, township 31 8., range 23 W. In this region the high 
prairie at the heads of the creeks is composed of the calcareous 
grit of the Loup Fork Tertiary, apparently very much thinner 
than at the head of the streams somewhat farther east. Near the 
head of the northwest fork of the West Branch Bear creek, the 
locality just named, there is an excellent exposure of the contact 
line between the Tertiary and the Dakota brown sandstone. From 
this point the sides of the small canyon down to the main creek 
are mostly rocky showing plenty of exposures of brownish and 
brownish-yellow sandstones with yellowish-brown to iron colored 
coarse sandy shales aggregating a thickness of about 75 feet. The 
lithologic appearance of the rock in this canyon as well as the 
general appearance of the rocks forming its sides and also the upper 
walls of the main creek suggest very forcibly the similar appear- 
ance in the ravines in the area of the Dakota sandstones of central 
Kansas. This is the thickest exposure of Dakota seen by the 
writer south of the Arkansas river. From general appearance prob- 
ably no one would hesitate seriously to correlate these sandstones 
with the Dakota of central Kansas. No fossils were found, but 
Professor Cragin has reported “meagre fragments of dicotyledonous 
leaves” from No. 2 of this section along upper West Bear creek 
which he called Dakota sandstone! 
Where the northwest fork joins the West Branch Bear creek, 
the upper part of the eastern bluff is composed of the coarse sand- 
stones and shales, just described as Dakota, which apparently rest 
unconformably on bluish shales of the Kiowa below. In the upper 
part of the Kiowa of this cliff are thin layers of yellowish shales 
somewhat similar to those in the superjacent Dakota sandstone, but 
running at a diiferent angle from the layers of the latter so as to 
Suggest the idea of unconformability. At the base of the cliff, how- 
ever, the layers of the Kiowa shales are nearly horizontal, so that 
perhaps the oblique structure of the yellowish arenaceous shales, 
alternating with clay shales, may be explained as due to cross- 
1 EF. W. Cragin, Bulletin Washburn College Laboratory Natural History, vol. IT, 
p. 77. Topeka. 
