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upland forest country. These belts of timber usually follow the direction of the stream divides, or sometimes appear in the valleys of the streams themselves, according to the depth of erosion of the latter.

North of Parker County, owing to the dying out of the Glen Rose Prairie in that direction, the Paluxy Cross Timbers merge into the main cross timbers, so that from there northward they form a continuous belt. The Paluxy Cross Timbers cease to be a conspicuous feature south of Leon River, coincident with the cessation (as a stratigraphic feature) in that direction of the sand bed in which they grow.

-We have mentioned the appearance south of Wise County of an intermediate belt of prairie between the two belts of forest which form the Western Cross Timbers. This prairie assumes increasing areal importance south, and forms an important accompaniment of the general region of the Lampasas Plain. Like the Walnut Prairie and the Western Cross Timbers, it is developed on the slopes of the western escarpment and in the streamway indentations of the Lampasas Plain, occupying large areas in Parker, Hood, Somervell, Erath, Comanche, Mills, Lampasas, Burnet, and Travis counties, and is seen typically around the towns of Granbury, Glen Rose, Stephenville, Comanche, and Lampasas.

The regolith is usually thin and shallow and the general tone of the landscape of a brownish-yellow color. The surfaces are usually stony, owing to the breaking down of the many thin ledges of limestone, which, in alternation with marly clays, compose their substructure. The Glen Rose Prairie is covered with a thin growth of short grasses. Thickets of sumac and occasional mottes of live oaks grow along the rocky ledges, and mesquite trees in the flattened areas. In places, for example the breaks of the Colorado, dense forests of juniper, locally called cedar, inhabit the rocky ledges. These vegetal features give to the country a diversified and picturesque aspect.

The minor configuration of the Glen Rose Prairie is broken by low relief features, consisting of low terraces and stratified benches resulting from the persistence of certain harder strata in alternation with beds of softer material. Low, circular buttes, seldom over 50 feet in height, consisting of alternations of thin beds of indurated arenaceous limestone and clay, are also frequent. These are seen near Lambeth and Stringtown, Parker County, and thence southward at many points on the eastern border of the Western Cross Timbers. They are especially well developed west of Lampasas and on the margins of the Colorado near the corners of Burnet, Blanco, and Travis counties.

From the foregoing brief description of the Black and Grand prairie regions of Texas north of the Colorado, it must be apparent that all the diverse features thereof result from the composition, degree of