Record of Geology of Texas, ISSY-ISOG. 
267 
White, iCtiarles A. 
isfcrata in which la eharaeteristic Ooal-mieas'nre fauna preYails, but which 
is not known to contain any fossils of the mesozoic types, if we except the 
Ammonites parkeri of Heilprin, which he states was obtained from Carbon- 
iferous strata in Wise county. Notwithstanding the mesozoic character 
of a part of the molluscan fauna of the upper formation, the preponderance 
of evidence makes it necessary to regard it as belonging to the great 
Oarboiniferous system, and as constituting an upper member of it. For 
these and other reasons yet to be stated I have little or no hesitancy in 
designating this Texan formiation ,as Permian, as Prof. Cope has done, but 
I shall briefly discusis in following paragraphs the propriety of the use 
of that name for all of the North American strata to which it has been 
applied.’^ Pp. 109-110. 
Permian strata blend with those of the Coal-measures. Description of 
the Texas Permian strata. Topography. Thickness of Permian strata. 
Vertebrate fossils. Thickness of Texas Coal-measures. Their characteris- 
tic invertebrate fossils. The ‘‘gypsum-bearing” beds — Triassic or Permian? 
The great conformable series of North Texas. Thicknes.s. Stratigraphic 
relations of the Texas Permian. Description of Texas Permian. List of 
invertebrate species. Summary. Brief' descriptions of three new Cephalo- 
pod ispeoies (Plate I). Commingling of Mesozoic and Paleozoic types. 
“The special interest which these Texan collections possess lies, flrst, 
in the presence of the two Cephalopods of the (Mesozoic type as members 
of an invertebrate fauna composed otherwise of paleozoic types ; and sec- 
ond, in the association of this invertebrate fauna with a vertebrate fauna 
composed mainly of Permian types, as determined by Professor Cope, and 
in the known superposition of the formation containing these faunas upon 
characteristic Coal-measure strata.” Pp. 119-120. 
The biological interdelimitation of the Mesozoic and Paleozoic ages. 
Attempts to explain the commingling of earlier and later types in one and 
the same stratum. Unphilosophical views concerning ehronological restric- 
tion. Discussion of North American and lEuropean Permian. 
“The recognition of the Permian, of Texas as a separate upper group of 
a strata belonging to the Carboniferous system is based upon both strati- 
graphical and Paleontological evidence, and this evidence is fuller than that 
which has been adduced in favor of any other reputed Permian strata of 
North America.” P. 126. 
427. 
Admimis'tratiYe Report, Division of Mesozoic Paleontology. 
Eiglitih Aninmal Repoiit of tlie D. S. Geol. Snrv,, Part I, pp. 
178-181. Waislbington, 1889. 
(Field Work in Texas), pp. 179-180. 
Instructions to Mr. Hill. “His work for the season was confined mainly 
to Grayson, Denton, Tarrant, Dallas, Comanche and Travis counties, but 
various other counties were visited. 
(Early in October I joined Mr. Hill at Austin and proceeded to review 
with him his field of work of the two preceding months and to make 
additional observations with reference to the objects of that work. In 
