The Pemberton Hill-Lewisville (T-2) terrace deposits of the Trinity River in Dallas and Denton Counties are divided into four consecutive members. Sixty-three vertebrates, 32 mollusks, and several insects and plants were collected from 3 members and are discussed in the report.

Forty-three species belonging to 28 genera, 12 species of brachipods belonging to 8 genera, and 1 species of gastropods are described from the Morgan Creek, Point Peak, and San Saba Members of the Wilberns Formation in the Llano Uplift.

The Blach Ranch and Breckenridge limestone members of the Thrifty formation are the most persistent mappable rock units in the Cisco group of the Brazos and Trinity River valleys.

Studies of physiographic relations and of fossil molluscan faunas made in the Pecos River valley region (Val Verde County to the Texas�New Mexico border) reveal extensive, well-pedimented surfaces southwest of the river extending from the Davis Mountains to near the present channel.