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.

The Devonian-Mississippian transition outcrops of central Texas are here described summarily and assigned to a new stratigraphic unit, the Houy Formation. The beds included are mainly Upper Devonian, but partly Lower Mississippian. Locally a basal fraction may be Middle Devonian. Although the deposits included are diverse and their associations complex, the maximum surface thickness so far known is only about 17 feet.

Pleistocene-age fossil horses of Texas belong to at least three faunal assemblages. The oldest contains Hippotigris (= Plesippus) which disappeared before Yarmouthian time. The second contains Equus scotti and Onager semiplicatus (= Equus (Asinus) calobatus) which disappeared before Sangamon time. Both these groups are found on the High Plains but not on the Coastal Plain or along the central Texas rivers, where a later fauna, probably of Sangamon age, is found which contains remains of Equus, Asinus, and Onager but no Hippotigris.