RED BEDS OF RIO GRANDE REGION 55 
ance to the sandstone which, in eastern Colorado and New Mexico, 
has frequently been called the lower Dakota, but which, as Stanton" 
has shown, underlies fossiliferous Comanche in the plains region, 
and in the foothills of the Rocky Mountains at Canyon City, Colo. 
This sandstone is followed in turn by fossiliferous sandstones, shales, 
and limestones representing the principal subdivisions of the Upper 
Cretaceous section of the eastern Rocky Mountain region, with the 
possible exception of the Dakota. 
In the central part of the region described, although known Car- 
boniferous Red beds were observed in several places with fossiliferous 
Benton in the same section, no red sediments were observed which 
could be referred to the Triassic. This fact is significant, since 
Triassic Red beds are known to occur in the Gallinas Mountains,? 
about 60 miles northwest of Galisteo canyon, and in the plains region 
of eastern Colorado and New Mexico, ‘Triassic vertebrates have 
been reported by Darton’ in the Red beds of Purgatory canyon in 
southeastern Colorado, and by Stanton‘ in the Rio Cimarron canyon 
of eastern New Mexico. The writer has also found them in the 
northern breaks of the Staked Plains in eastern New Mexico. 
The latter occurrence has not heretofore been described. The 
fossil bones were found at E, O. Davis’ ranch, about 20 miles south- 
east of Tucumcari. They occur at the top of the Red beds, overlain 
at this point by plains-Tertiary, but covered half a mile farther north 
by yellow sandstones and shales containing Gryphaea corrugata Say 
and other characteristic Comanche fossils. 
Invertebrates of probable Triassic affinities have been reported 
from the red beds of the Canadian valley by Stanton,5 who in com- 
pany with the writer obtained a collection of them at Henry Hunikes 
ranch on the Rio Concho, about 30 miles southeast of Las Vegas. 
tT. W. Stanton, ‘‘The Morrison Formation and Its Relations with the Comanche: 
Series of the Dakota Formation,” Journal of Geology, Vol. XIII (1905), pp. 657-69. 
2 E. D. Cope, Monographs, U. S. Geographical and Geological Surveys West of 
tooth Meridian, Vol. IV, Part II, “Report upon the Extinct Vertebrata Obtained in 
New Mexico by Parties of the Expedition of 1874, 1877,” pp. 5-13. 
3N. H. Darton, ‘‘Preliminary Report on the Geology and Underground Water 
Resources of the Central Great Plains,”’ U. S. Geological Survey, Professional Paper 
No. 32, 1905, p. 159. 
4 Op. cit., p. 665. 5 Ibid., p. 666. 
