388 



University of California Publications. [Geology 



the formation of the former deposits and it likewise is one of the 

 abundant forms of to-day. Its scarcity in the Samwel Cave 

 deposits was due probably to some one of the factors which 

 brought about the entombment of the Samwel Cave remains. 



CATHABLSTA SHASTENSIS, n. sp. 

 Type specimen no. 8603, Univ. Calif. Col. Vert. Palae., tarso- 

 metatarsus from Potter Creek Cave, California. General char- 

 acters of Catharista occidentalis Miller, but more robust; foot 

 rotated inward upon the shaft. Comparison is here made with 

 an average specimen of C. occidentalis from Rancho La Brea. 



The two specimens of the tarsometatarsus of C. 

 occidentalis and C. shastensis are much the same in 

 osteological characters. In total length the cave form 

 is but five-tenths millimeters the shorter, a fact which 

 greatly facilitates the comparison of proportions. 

 Seen from in front, the most striking character afforded 

 by the new form is the greater degree of robustness. 

 In the head region, greater width increases the blunt- 

 ness of the intercotylar tuberosity and the roundness 

 of the dome-shaped cavity into which the proximal 

 foramina open, as well as the width of the septum 

 between these two foramina. 



The shaft is much wider at its middle portion, so 

 much so that the graceful taper toward a narrowest 

 point slightly below the middle, that is seen in C. 

 occidentalis is entirely lost. As noted in a study of 

 the condors, 3 the tarsometatarsus of the young cathartid 

 seems to differ from that of the adult individual by 

 its greater slenderness of shaft in proportion to the 

 width of the articular surfaces. The natural objec- 

 tion that the type specimen of the proposed new 

 form might merely represent a more mature indi- 

 vidual is controverted by the fact that its proximal 

 foramina are less completely closed than in the speci- 

 men of C. occidentalis with which it is compared, a 

 condition indicative of youth rather than of age in 

 the individual. 



The elevated inner border of the anterior face of 

 the bone in C. shastensis drops backward as it passes 

 down the shaft, thus giving the appearance of an 

 inward rotation of the foot upon the shaft. This con- 

 dition is more marked in the form under discussion 

 than it is in C. occidentalis. Other differences are 



Fig. 1. Catharista 

 shastensis, n. sp. 

 Tarso metatar sus 

 no. 8603, Pleisto- 

 cene of Potter 

 Creek Cave, Shasta 

 County, California. 

 Anterior face, ap- 

 proximately natural 



3 Miller, L. H., Univ. Calif. Publ. Bull. Dept. Geol., vol. 6, p. 1, 1910. 



