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University of California Publications in Geology [Vol. 8 



verse and the sagittal diameters have been appreciably reduced and 

 surface markings have been entirely lost. The robustness of the 

 bone is still in excess of that of Gavia stellata and its length sur- 

 passes the average of lengths recorded for the tarsus of G. immer. 

 It would seem incongruous to attempt to associate this large, stout 

 tarsus with the slender femur described above. The species which it 

 represents probably did not materially differ from the existing Gavia 

 immer ( Briinnich ) . 



In the discussion of the fossil avifauna of the Pacific coast of 

 North America (loc. cit.) comment was made upon the absence of 

 Gaviidae from horizons thus far explored. The two specimens re- 

 corded above show the family of loons to have been well represented 

 in California during the deposition of the Upper San Pedro Beds. 



SYNTHLIBORAMPHUS ANTIQUUS (Gmelin) 



This species is represented by a single coracoid in perfect condi- 

 tion. Comparison was made with a series of specimens in the collec- 

 tion at the State Normal School at Los Angeles and in the Museum 

 of Vertebrate Zoology of the University of California. The series 

 included specimens of Brachyramphus, Ptyckoramphus, and the 

 present species. 



DIOMEDEA near NIGEIPES Audubon 



The genus Diomedea is represented by a single specimen, the 

 badly water-worn tarsometatarsus of a bird approximately the size 

 of D. nigripes. The extreme proximal end including the hypotarsus 

 is lost and the surface of the bone everywhere is badly corroded. 

 The osteologieal characters are lost so far as minor details are con- 

 cerned. The length of the bone is markedly less than that of nigripes 

 and, despite the extensive reduction from wave action, the diameter 

 of the shaft is noticeably greater in all directions. 



Further comparison was made with the Laysan Albatross, a 

 skeleton of which was kindly donated by Mr. George Willett of the 

 United States Biological Survey. This extralimital species is much 

 smaller than the fossil specimen in all except total length. The latter 

 measurement is but slightly less than in the fossil form. 



More perfect material would in all probability prove the Pleisto- 

 cene specimen to belong to a distinct species. 



