COPE ON NEW EXTINCT VERTEBRATA. 387 



Aiitero-posterior diameter proximally 0.021 



Autero-posterior diameter at middle , 0.008 



Autero-posterior diameter of median trochlea 0.010 



Autero-posterior diameter of internal cotylus 0.011 



Length, No. 2 0.081 



Transverse diameter of all the trochlete at their middles 0.017 



Length, No. 3 0.085 



Transverse diameter of trochlete 0.019 



This species appears to have been coinmou in the Pliocene of Oregon, 

 where it was discovered by Charles H. Sternberg. In measurements it 

 considerably exceeds the G. dilophuSj which is, according to Professor 

 Baird's diagnosis,* the largest of the North American species. With 

 this bird, the extinct G.idahensis Marsh nearly agrees in measurements, 

 exceeding a little the corresponding parts of the living bird. These I 

 have had the opportunity of studying through the great courtesy of the 

 Direction of the Smithsonian Institution. The specimen examined is 

 No. 11120 of the Smithsonian Catalogue. 



Anser hypsibatus, sp. nov. 



A single tarso-metatarsas, perfect except in the hypotarsus, represents 

 this goose. It is nearest to the A. canadensis among American geese, 

 and I compare the specimen with the corresponding bones of three 

 individuals of that species, two of them cotemporary fossils, and one a 

 recent bird, No. 11086 of the Smithsonian Catalogue. For the use of 

 the latter I am indebted to Professor Henry. 



The element mentioned is longer and more slender than that of the 

 A. canadensis, and differs in a varietj^ of points from that bird. The 

 proximal two-fifths of the shaft is more deeply grooved, and the lateral 

 ridges are more prominent. This is especially true of the external 

 angle, which continues straight to the anterior border of the diaphysis, 

 where it is wanting or weak in the A. canadensis. The external side is 

 also plane, or nearly so, to this angle, while in the existing bird it is 

 swollen, having a narrow convex surface, which passes insensibly into 

 the anterior and posterior faces. This character continues to distin- 

 guish the external faces of the shaft of the bone to near the distal ex- 

 tremity in the two species. The angular posterior edge of the inner 

 face is more prominent than the corresponding and fainter posterior 

 border of the inner face. From this it folio vvs that the posterior face of 

 the shaft at its middle is oblique, sloping forward and inward. In A. 

 canadensis it is plane or gently convex. The superior part of the pos- 

 terior face is oblique in the opposite direction, and is much narrower 

 than the corresponding face in A. canadensis. 



Measurements. m. 



Length of bone 0.087 



j proximally : 0.016 



Transverse diameter < medially 0.006 



l^distally 0.018 



Width of internal cotylus 0.007 



* U. S. Pac. R. R. Surveys, ix, p. 877. 



