This paper brings part of the classification of upper Albian ammonites up to date and up to modern standards for some of the Texas species. Twelve new species are described (Drakeoceras georgetownense, D. drakei, D. arringtoni, D.kummeli, D. gabrielense, D. dellense, D. lasswitzi, Durnovarites adkinsi, Deiradoceras amsburyi, Pervinquieria whitneyi, P. smedalae, Prohysteroceras, P. atchisoni) and two previously described species are redescribed.

In the Great Plains the succession of gross ecological conditions through Neogene and Quaternary time may be interpreted from the stratigraphy, geomorphological history, buried soils, and fossil mollusks and plants. A mild humid climate prevailed over a late-mature erosional topography in earliest Neogene. Progressive reduction of topographic relief and lowering of the regional water table, accompanied by an almost uniform drying of the climate, followed. Semiarid, rigorous conditions existed on the constructional plain, temporarily at erosional equilibrium, at the end of the Tertiary.

Uranium was discovered near Tordilla Hill in Karnes County, south-central Texas, in the fall of 1954, in the upper part of the Jackson formation of late Eocene age. By July 1955, 14 uranium prospects were reported as far northeast as Fayette County, northeast of Karnes County, and southwest to Duval County, south Texas, over a distance of about 190 miles. Uranium minerals or radioactive rocks have been found in tuffaceous sand, silt, or bentonitic clay in at least seven different stratigraphic positions ranging in age from late Eocene to Pliocene.

The lead and zinc deposits in the Upper Cambrian rocks of central Texas are reviewed in the light of new detailed information. Included are analytical data for all deposits, detailed stratigraphic sections of the Cambrian rocks, and maps at a scale of 4 inches to the mile. Igneous rocks of Carboniferous or younger age in the area are recognized for the first time.