88 University of California Publications in Geology [VOL. 7 



clearly indicate a bird generically distinct from Cathartes and the 

 improbability of the occurrence of a true Vultur in North 

 America is extreme. ' ' 22 With the former point at least there can 

 be no possible disagreement after a consideration of Cope 's figures 

 of Palaeoborus. Whether the form may be considered cathartine 

 at all is open to. very serious question. Lucas 23 considers it as 

 more probably of polyborine affinities. 



In South America fossil cathartids are less rare. Cathartes 

 and Gyparchus are reported from the Pleistocene caves of 

 Brazil. 24 Moreno and Mercerat 25 describe two species from the 

 Pampean Pleistocene and three from the Pliocene of the Santa 

 Cruz. The Pleistocene species, Cathartes fossilis and Sarco- 

 rhamphus fossilis, represent genera still existing in that region. 

 The three species from the Santa Cruz, Psilopterus communis, 

 P. australis and P. intermedius, belong to an extinct genus which 

 is placed by the authors adjacent to Cathartes and is considered 

 by them to be intermediate or transitional between that genus 

 and Sarcorhamphus. The three species of Psilopterus are based 

 on the most fragmentary material. The figures are such as to 

 indicate specimens in rather poor state of preservation as to sur- 

 face markings. Trochleae are corroded away and intermuscular 

 lines are entirely wanting. P. intermedius is based on a single 

 specimen consisting of two tarsal trochleae. The other two 

 species are based upon fragmentary tarsi poorly preserved. 

 While there may be no question in the minds of these authors 

 as to the relationships of the genus Psilopterus, there appears 

 nothing in the lithographed figures or in the very meager descrip- 

 tions that is at all convincing. 



Beyond the above instances, the only record of fossil cath- 

 artids previous to the excavations at Rancho La Brea is the 

 remarkable specimen made known by Gaillard 26 from the phos- 

 phorites of Quercy, an Oligocene horizon in France. This species, 



2-2 Coues, E., Key to N. Am. Birds (ed. 2; 2884), p. 822. 



23 Lucas, F. A., in Zittel's Text-Book of Palaeontology, Eng. trans., vol. 

 2, p. 277, 1902. 



24 Winge, O., Fugle fra Knoglehaler i Brazilien, Museo Lundii, 1887. 



25 Palae. Argentina, An. Mus. La Plata, pt. 1, p. 67, 1891. 



26 Gaillard, C., Ann. de 1 'Univ. de Lyon, n. ser. 1, Sc. & Med., fasc. 23, 

 1908. 



