Recoed of Geology of Texas, 1887 - 1896 . 
269 
White, 'Charles A. 
northern Mexico. More ahoindant collections of fossils have been obtained 
in Texas than elsewhere. (Contrast between the Lower Cretaceous of the 
Southwest and the Upper Cretaceous. The Paleontological contrast. Want 
of faunal relationship between the Upper and Lower Divisions. The chro- 
nological hiatus. The Comanche of Lower Silurian strata of Texas east 
of the Pecos River ; Character and Thickness. The same west of the Pecos 
and in Mexico. Displacements involving other strata. Stratigraphic 
sitructure of the Sierra Sian Carlos in Chihuahua. Structure of the Chinate 
Mountains of Texas. No satisfactory proof that the Jura and Trias are 
represented by any North American strata south of the 34th parallel of 
‘ latitude. 
429. 
Remarks on the Cretaceous of ISroTthern Mexico. 
Proe. Amer.' Assoc. Adv. of Science, Vol. XXXVIII, p. 252. 
1890. 
“In these remarks the speaker referred to observations made during his 
late visit to the State of Chihuahua, Mexico, and to the adjacent parts of 
Texas and New Mexico. A small range of mountains in Chihuahua, sev- 
enty-five miles sioutheaisitward from Presidio del Nor-te, knovvn as the Sierira 
San Carlos, was found to be composed almost wholly of much disturbed, 
compact, bluish limestone strata having the usual aspect of the Carbon- 
iferous limestones of the great interior region. They were found, however, 
to contain Cretaceous fossils from top to bottom, the recognized species 
being such as characterize the Comanche Cretaceous of Texas. '''■ * 
“The isolated mountain near Presidio del Norte was also found to be 
composed of the Comanche limestone; and lying upturned against its 
southern base and extending far to the southward, is a great thickness of 
shaly strata, succeeded by sandstones, the former bearing fossils of the 
Colorado Croup, and the latter those of the Pierre-Pox Hill Group. 
^ 
“In the Chinate mountains in Texas, about twenty-five miles north of 
Presidio, the bluish Comanche limestone rests ooinformably upon Carbon- 
iferous limestone, the color and character of both being so similar that 
they are distinguishable only by their .respective fossils. Here of course 
both the Jura and the Trias are absent. In both the Chinate and the San 
Carlos mountains, the Comanche limestone is silver-bearing at its base.'” 
430. ^ 
Administrativ’e Report, Division of Mesozoic Invertebrates. 
Xinth Annnal Report of the D. S. Genlogical Snrv., pp. 120- 
123. Waishdington, 1890. 
Field investigations in Texas, p. 120-121. 
“From the city of Dallas as a center, I extended these field observations 
into the neighboring counties of. Tarrant, Denton, Kaufman and Navarro. 
This work consisted of an investigation of the stratigraphic relations of 
the formations occurring in that region with one another and with those of 
