A vertebrate fauna from late Tertiary beds near Frazier Mountain, California

• Main Author: Bass, Manuel N.
• Format: Others
• Published: 1951
• Online Access: https://thesis.library.caltech.edu/5553/1/Bass_mn_1951.pdf; Bass, Manuel N. (1951) A vertebrate fauna from late Tertiary beds near Frazier Mountain, California. Master's thesis, California Institute of Technology. doi:10.7907/7368-BM35. https://resolver.caltech.edu/CaltechTHESIS:02262010-100255584 <https://resolver.caltech.edu/CaltechTHESIS:02262010-100255584>

From 1932 to 1950 vertebrate fossils were collected in the Hungry Valley area located in the northern half of the Black Mountain quadrangle, California. The fauna described in this paper was found between horizons approximately 350 feet below and 600 feet above the division established by Crowell separating the Hungry Valley formation and the Peace Valley beds. Fragmentary fossils and nature of the beds in which found suggest lake and alluvial fan deposits. The fauna is a typical plains fauna except for the absence of carnivores which were presumably present but found easy prey on grasslands well removed from the sites of deposition. Perissodactyls, among which are at least two species of Pliohippus (including the new species P. crowelli), a Neohipparion?, a tapir and a rhinocerotid, dominate the assemblage. Artiodaotyls include a new species of llama-like camel, Tanupolama? montis, as well as a larger camel and an antilocaprid. The vertebrate-bearing strata overlie beds dated by Axelrod as middle Pliocene on the basis of plant remains. Crowell regarded the Peace Valley beds as middle Pliocene and the Hungry Valley formation as largely upper Pliocene. P. crowelli although apparently more advanced than P. spectans, is regarded as belonging to the Hemphillian stage. Largely on this basis, the Peace Valley beds and several hundred feet at the base of the Hungry Valley formation are referred to middle Pliocene; the bulk of the Hungry Valley formation is presumably upper Pliocene. This conclusion is in accord with the view that North American rhinoceroses became extinct by the close of the Hemphillian stage.