16 R. W. Shufeldi 



some respects these differences are no greater than we would meet 

 with in the case of two individuals of the same species. 



The distal transverse diameter of the condyle is identically the 

 same in both. In form and relative size the condyles agree in the 

 two forms almost exactly. The characters of the anterior tendinal 

 groove agree; while in both forms the antero-posterior flattening of 

 this part of the shaft is the same. Where the condylar crests are more 

 prominent in Hesperornis, they have been broken off in Marsh's 

 Coniornis alius, and this likewise applies to the elevation for tendinal 

 attachment on the anterior aspect of the shaft on the outer side of 

 the tendinal groove, above the external condyle. 



Why the specific name of alius should have been bestowed upon 

 this fossil bird, it is not for me to say; the fragment of its skeleton 

 does not offer a sufficient reason for it. 



In my opinion, Coniornis alius of Marsh is but another species of 

 Hesperornis, and one closely related to H. regalis. Furthermore, from 

 such indications as we may legitimately consider, and which are pres- 

 ented on the part of the fragment at hand, it was a form nearly as 

 large as Hesperornis regalis, and henceforth it should be relegated to 

 that genus and bear the name of Hesperornis alius. 



In instituting comparisons Hke the above, the fact must ever be 

 borne in mind that in all birds their skeletons present certain individual 

 variations, in addition to those which are due to sex and age. This 

 is especially true with respect to Loons, Grebes, Divers and their 

 allies, and it is fair to presume that, in the genus Hesperornis, the 

 same variations were to be found; while in the case of fossils of great 

 age, distortion due to pressure must always be taken into account. 



Genus Graculavus Marsh. 



{Plate VI, Figs. 33, 34; Plate VII, Figs. 49, 53; Plate XIII, Figs. 91-93; Plate XV, 



Figs. 125-127.) 



Marsh, Amer. Joum. Sci., ser. 3, III, 1872, 363. 



In the collection of the Peabody Museum, Yale University, of 

 fossil birds, I find the following types of the genus Graculavus of 

 Marsh, and other material referable to it: 



Graculavus velox. 



Graculavus pumilus. 



Graculavus anceps. 



Graculavus agilis. 



Graculavus lentus. 



Graculavus, [sp.?] 



