156 
Transactions Texas Academy of Science. 
Hill, Egbert T. 
“In tMsi paper it is proposed to give a brief elassiflcation of the topo- 
graphic and geologic features of the extensive area of Texas. Evidently so 
brief a mention of this vast region will be neither exhaustive nor detailed ; 
It is a preliminary statement of some of the great features which will be 
more accurately delineated by those who, v/ith better facilities, will here- 
after conduct accurate surveys of this region, which has as yet been only 
partially reconnoitered.’’ 
217. 
(Classification and Origin of the Chief G-eographic Featnres of the 
Texas Eegion. II. 
Amer. Geologist, Yol. Y., pp. 68-80. Minneapolis, Feh., 1890. 
Contents: The Valleys of Erosion: The Older Valley of the Canadian: 
The Older Valley of Red Riv®i% The River Terraces of the Black Prairie 
and Eo-Lignitic Regions. The Lake Basins of the Trans-Pecos Mountain 
Region. (Moiuntainous and Disturbed Regions: The Ouachita Mountains ; 
The Mountains of the Trans-Pecos Country. Epitome of the Chief Topo- 
graphic Areas of the Texas Region. (Tabulated.) 
218. 
Eeport of. 
First Ann. Eept. Geol. Siirv. of Texas, 1889, pp. Ixxxiii- 
Ixxxviii. Austin, 1890. 
Administrative Report to the State Greologist. Geographic and Topo- 
graphic Work. iStratigraphic Work. Reconnoissiance. Cross-lSection 
Work. Economic Investigations. Illustration- Office Wiork. Work of 
Assistants: Mr. J. A. Taff ; Mr. N. P. Drake; Mr. C. C. MoCullough; Mr. 
J. S. stone. 
“In accordance with your request upon organization of the Survey, I 
undertook, in February, 1889, * * the study of the natural features 
of those portions of the (State known as the Black and Grand Prairie 
regions and the accompanying Upper and Lower Cross Timbers, all of 
which are the surface features of the Cretaceous rocks, to which they owe 
their topographic individuality, economic possibilities, and conditions for 
human habitation. 
-X- * -X X X 
‘The extent and character of the region to be surveyed * * em- 
braced an area of over 7i2,512 square miles, or over one-fourth (27.75 per 
cent.) of the total area of the (State — .a region three times as large as the 
combined area of Massachusetts and Connecticut, Rhode (Island, New Jer- 
sey, and Delaware, or three times the size of West Virginia. Since it 
would have been a physical impossibility for the whole force employed 
upon your Survey to have covered this enormous area with even a recon- 
noissance, it became a matter of necessity that the region should be 
divided into wmi’king districts, and the work of my assistants limited to 
soime certain portion. 
“In accordance with the necessity, the total area was subdivided, there- 
