Record of Geology of Texas, 1887 - 1896 . 
171 
Hill, Robert T. 
and used by writer. Not the Denison beds of Taff, as used in an entirely 
differeiiit meaning. Compare Bulletin of Geological (Society of America, 
Vol. n, p. 591, and Third Annual Report of Texas State Geological Sur- 
vey) of liiis Washita Division, certain features which led him to believe 
that his eaa-ly diagnosis of the Tucumoaid beds was erroneous, and that 
they were really closely allied in age to the Denison beds. lUnder this im- 
pression, wbicli was connnunicated orally to all interested, he availed him- 
self of the first opportuiuty to revisit Tucumcari, April 30, 1801. He then 
discovered in asisoeiation with G. (lilatata tlie list of additional species here- 
with given, and, at earliest opportunity, under date of May, 1892, pub- 
lished, in a general discussion of the region, the following revision of his 
previous conclusionsi, which was the first printed announoement of the 
Cretaceous age of the G. dilatata beds: — 
‘‘the trinity sands and red bed regions. 
“Tlie writer has twice visited the Mesa Tueumoari and found it a most 
interesting geological remnant of the former area of the Llano Estacado, 
The table or summit described by Capt. Simpson is covered with the typical 
Llano Estacado formation, identioal in oomp'osition and formerly contin- 
uous with the sheet wiiich covers the Llano proper, some 20 miles distant. 
Belo'W this is a vertical escarpment of 50 feet or more of typical 
Dakota sandstone resting upon loose sands and clays, forming a slope iden- 
tical in aspect and fossil remains with the Denison beds of the Washita 
Division, which have been eroded away from the 400 miles intervening 
between it and the main body of those beds at Denison, Texas. Beneath 
this is a large deposit of the typical Trinity sands country of (Eor “country 
of” read “cohsisbing of” — ^a typographical error.) .white pack sands, thin 
clay seams, and flagstones, while the base is composed of the typical Ver- 
million sandy clays of the Red Beds.” 
Misquotation in the Third Annual Report of the (Texas) Geological 
Survey, and in Science of May 26, 1893, p. 283. 'Outline of the region and 
its broader problems in Bulletin of the Geological 'Society of America enti- 
tled “Notes on the Texas-New Mexico iRegion.” iSeetion of Tucumcari 
Mesa. List of Eossils. List of fossils published in the Texas Reports. 
“Einally, the writer wishes to state that he is not prepared, nor does he 
desire, to write a final treatise on 'the Tucumcari, which can never be 
properly related until the atlas-sheets of the United .States Geological 
Survey are completed for the region. Tucumcari is but a single sta- 
tion in the vast group of phenomena belonging to the deposition and 
degradation of the Las Vegas and Llano Estacado Plateaus and the Cana- 
dian Valley, and to be properly understood it would be necessary to write 
a treatise on the whole region. One thing is settled beyond all doubt in 
my mind, however, and 'that is that the Cr. dilatata beds of the region do 
not belong to the Jurassic, but are undoubtedly of Cretaceous age. On the 
other hand, it may also be safely assumed that the Gryphsea dilatata, Sow. 
of Marcou, is not the sa.me ns G. piteheri, Morton, as has been asserted by 
many autlrors, nor does it occur in the Cretaceous beds of Central Texas, 
so far as the winter is aware. But this is a question which cannot be 
discussed intelligibly until la thorough revision of the Grypseas is made. 
