58 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
to Chicago, Chicago to Cheyenne or to Mobile, or from New York to Jacksonville, 
Fla. The resident of the western part of Texas is nearer San Diego, Cal., than to 
his own State capital, or more than 200 miles closer to the Pacific than to the Gulf of 
Mexico. It extends through more than 10 degrees of latitude (25° 50' to 36° 30' N.) 
and through more than 13 degrees of longitude (93° 20' to 106° 40' W.). 
CLIMATE. 
The climatic conditions presented by a region so vast as this must necessarily be 
very diverse. The State has been divided into five climatic and topographic divisions, 
as follows : 
1. The coast plain region . — This includes a strip along the coast and extending 
back from 150 to 200 miles, the western boundary being marked approximately by a 
line drawn through Laredo, San Antonio, Austin, Palestine, and Texarkana. Immedi- 
ately along the coast it is more or less marshy, and the eleyation nowhere probably 
exceeds 500 feet. This region receives an abundance of rainfall; at Galveston it 
amounts to 52 inches and at Palestine to 47 inches. 
2. The black prairie region. — This is a narrow belt running parallel with the coast 
plain, and is chiefly characterized by the rich black soil of the undulating prairie. 
The elevation is 300 to 700 feet, and the mean annual rainfall is probably not over 35 
inches. 
3. The central region . — The central region extends westward from the longitude of 
Denison to the eastern escarpment of the Llano Estacado and southwest to the moun- 
tains of the Trans-Pecos region. In its northern part are forests of stunted growth 
called “cross timbers,” which lie between the Bed and Brazos rivers. Westward, 
between the one hundredth meridian and the escarpment of the Llano, are the “ red 
beds,” a gypsiferous region not unlike that just east of the Black Hills in South Dakota. 
The southern portion of the central is a broken country of limestone formation, and 
in some parts devoid of streams. The altitude of this region is from 700 to 2,500 feet, 
and the annual rainfall is probably about 25 inches. 
4. The Llano JEstacado. — The Staked Plains extend from near the Canadian River 
on the north to the thirty-second parallel on the south. This is an immense plateau with 
a gentle inclination from northwest to southeast. The elevation above the Gulf is from 
2,600 to 4,800 feet. They extend from the Pecos region in New Mexico eastward to near 
the one hundred and first meridian, where they are terminated by a bold escarpment on 
the northeast, east, and southeast. On the eastern side extensive canyons penetrate the 
Plains to various distances, running from northwest to southeast, in a line with the dip of 
the strata. The Colorado, Brazos, and Red rivers all have their sources in the Plains 
with numerous branches extending into them a greater or less distance, some of them 
as far as 100 miles. These canyons are the work of erosion, and no greater force was 
required than that now at work. When once the upper stratum is broken and the 
water begins to flow over the soft beds below, the channel is cut deeper each year 
until the present deep canyons have resulted; all have flowing streams in them, 
coming from the water-bearing stratum lying at the bottom of the Tertiary formation. 
The sides of these canyons are usually precipitous, and they are consequently difficult 
to cross. At various places in the Plains are permanent lakes of greater or less area, 
some fresh and some salt. Besides these there are numerous depressions or basins in 
which water collects during the rainy season and remains for several months. These 
lakes often cover several hundred acres. 
