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University of California Publications in Geology [Vol.7 



Relation to Nothrotherium shastense. — The mandibular ramus 

 from Potter Creek Cave, although belonging to an adult indi- 

 vidual, is shorter than the lower jaw in the Raneho La Brea 

 species. The well-defined and open sutures in the skull of the 

 latter species seem to indicate a young adult. 



Specimen 8202 from the Shasta cave is a first superior tooth 

 of the left side, which fits almost perfectly into the first alveolus 

 of the Raneho La Brea skull. It is a small tooth with posterior, 

 face slightly convex longitudinally and lateral faces furrowed. 

 Its anterior half is decidedly smaller transversely than the 

 posterior half. No. 8702 s is a second superior tooth of the right 

 side. The outline of its triturating surface is very similar to 

 that of the Raneho La Brea specimen 10485, which is assigned 

 to the same position. Its inner face is, however, longitudinally 

 concave. The last superior alveolus of the left side in the Raneho 

 La Brea skull indicates a tooth wider on the inner or lingual 

 side and with a more rounding outer face of less width than is 

 shown in the corresponding tooth of N. shastense. 9 Tooth 8337 10 

 probably belongs to the inferior dentition. 



Judging from the evidence presented, there is reason to 

 believe that the Raneho La Brea and Potter Creek Cave speci- 

 mens represent distinct species. Nothrotherium teeth have been 

 found also in Samwel Cave, Shasta County, California. 



NOTHROTHERIUM ( ? ) , sp. 



The second phalanx upon which this tentative determination 

 is based, was obtained by Dr. L. H. Miller and Dr. F. C. Clark 

 from the Upper San Pedro beds exposed just behind the yard 

 of the San Pedro Lumber Company at San Pedro, California. 

 A single dermal ossicle was also found in these deposits. The 

 marine Pleistocene fauna of these beds was described by Arnold 11 



» Sinclair, W. J., New Mammalia from the Quaternary Caves of Cali- 

 fornia, Univ. Calif. Publ. Bull. Dept. Geo]., vol. 4, 1905, pi. 23, figs. 3 and 

 3a. In fig. 3 the lower margin of the tooth is the anterior margin; in 

 fig. 3o the anterior face is shown. 



o Sinclair, W. J., op. cit., p. 154, pi. 23, fig. 8. 



i(> Ibid., pi. 23, figs. 5 and 5a. 



ii Arnold, R., The Palaeontology and Stratigraphy of the marine 

 Pliocene and Pleistocene of San Pedro, California, Mem. Cal. Acad. Sci., 

 vol. 3, pp. 420, pis. 37, June, 1903. 



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