Echinoidea

29 p., 4 p. of plates : ill., col. map ; 27 cm.Includes bibliographical references (pt. 1, p. 13; pt. 2, p. 28-29).pt. 1. The Dudley Expedition / by Barnum Brown. The Harrar Plateau. Crystalline basement. The Adigrat sandstone. Upper Jurassic limestones. Cretaceous deposits. Nubian sandstone(?). Tertiary and Quaternary deposits. The Dirre Daua region. The Hargeisa, British Somaliland, region -- pt. 2. Echinoidea / by Ethel D. Currie. Jurassic Echinoidea from Ethiopia. Cretaceous Echinoidea from Ethiopia. Eocene Echinoidea from British Somaliland