312 The American Geologist. November, isos 
With the exception of the first two these have been referred repeat- 
edly to the Cretaceous (Washita and Fredericlisburg divisions) in Texas. 
The discovery in the same strata of a fossil angiospermous plant, 
which Mr. Cuniniins' figures and describes under the name Sterculia 
drakei is considered sufllcient evidence of the Cretaceous age of the 
strata from which it came. 
The sections here compared and thouuht to belong to the Cretaceous 
are as follows: 
Piiramiil Mitunlain 'I'unuiicun Numnta'm 
by Mu. MAitcor. by Mr. Cummins. 
1 Wliite limestone 2 feet 1 White clayey limestone 21) feet 
2 Yellow limestone ">0 " 2 Massive sandstone 60 '• 
3 Blue clay :W " :! Slial.M blue clay? N. H. W.) m " 
4 White sandstone 25 " 1 Massive yellowish sandstone. . .235 " 
5 Yellow sandstone 80 " 5 Ked sandstone 30 " 
6 White sandstone 8 " (i Blue clay 4 " 
7 Grayish l)lue clay 1 " 7 Pnrple clay H " 
S Varieii-ated marls 50il " S Arenaceons clay 1 " 
!• Bine clav 4 " 
Total (ii)(i feet Id Pnrple clav Ki " 
11 Light red clav 30 " 
12 Dark red clay 145 " 
Total 601 feet 
These sections are about ten miles apart, according to Mr. Cummins, 
but they are found in a region that embraces several other similar hills 
all of which arre referred by both Cummins and Marcou to the same 
geologic horizon. If we understand, contrary to the statement of Mr. 
Cummins,* but apparently in harmony with his general argument, that 
the "blue clay" horizon (No. 3 above, of Marcou) is the stratigraphic 
equivalent of his "shale" horizon (No. 3, of his Tucumcari section), and 
not of his No. 6, and ignore the enormous thickening of Mr. Cummins' 
No. 4 (his supposed '^'rinity sands), these sections present a reasonable 
degree of stratigraphic resemblance. We infer also, as argued by Mr. 
Cummins, that in Mr. Marcou's section the word "limestone" in No. 2 is 
a misprint for sandstone. The thickening of the sandstones of Cum- 
mins' No. 4, which may be considered the equivalent of Marcou's Nos. 
4, 5 and G, is not an unwonted circumstance in the composition of 
coarsely fragmental formations. 
The settlement of the disagreement will have to depend on the fossils. 
In the light of the fossils named by Mr. Cummins, the beds seem to be- 
long to the lower Texas Cretaceous,, but the question is not settled 
whether the lower. Texas Cretaceous, particularly the Trinity sands, is 
Cretaceous or Jurassic. Mr. Hill, who revolutionized the Cretaceous in 
Texas by adding to it the Comanche series including this member, has 
given a list of its molluscan fossils in his Arkansas report,t remarking 
that they bear "remarkable resemblance to forms from the upper Pur- 
beck and basal Neocomian or Wealdeu beds of Kurope." Mr. Marcou 
has reviewed this list of fossils;}: and made such changes in the identifi- 
catiojas that they are all made to appear Jurassic. In short, Mr. Marcou 
*"The only bine clay bed in the vicinity is that in which the fossil zone of the Gnj- 
pluea dUaldia \ar. t>inimc(iri occurs." p. 202. 
\Neoozoic Geoloqij of Kotith ivcxtcrn Arkansas. C/idp/cr •cii/. Annual report of the 
Geological Surveyof Arkansas for 1888, Vol. i:, leSO. 
i.\MEKicAN Geolooist, \'o1. IV, Doc, 18Si>, pp. 35"-3')T. 
