292 Shufeldt, Remains of Hesperornis. [july 



the prezygapophyses are buttressed by a sharp-edged ridge of bone 

 extending from above the stump of the rib facets somewhat ob- 

 liquely inward and upward, in 1499 there is in this place a distinct 

 transverse crease instead of a vertical buttress. A rounded vertical 

 forward margin in place of the sharp-edged buttress characterizes 

 the other three Yale specimens, and the crease in 1499 may have, 

 been accentuated if not caused by the slight vertical crushing to 

 which the bone has been subjected. 



" Such distinctions as I can see are certainly not generic, and so 

 far as the actual bones go, specific contrasts are hard to find. The 

 distinctions between Lestornis crassipes and Hesperornis regalis, 

 for instance, lie in other bones than this vertebra, so that had I the 

 23d vertebra? alone for comparison, I could hardly distinguish them 

 specifically — certainly not generically. I am sure the new bone 

 is that of a species of Hesperornis, possibly new, though this belief 

 is based mainly on geographic rather than on anatomical distinc- 

 tion. 



"The bone No. 1499 is not specifically determined if it is not 

 H. regalis." 



With reference to the exact locality, where this vertebra was 

 found, and other data, Mr. Charles W. Gilmore has given me the 

 following valuable and interesting information. "The vertebra 

 (Cat. No. 8199) was found by Dr. T. W. Stanton on Dog Creek, 

 Montana, on the left hand side of the valley about one mile above 

 its mouth. The bed from which the vertebra was collected is now 

 assigned to the Claggett formation because it is marine, while the 

 overlying Judith River deposits are freshwater with a few inter- 

 calated brackish-water beds. 



"The specimen is from the upper yellowish sandstone from a 

 fossiliferous band containing numerous sharks' teeth, vertebrae 

 and teeth of other fishes. 



"The only other bird remains known from this area is the type 

 of Coniornis altus, reported by Hatcher * as coming from ' near the 

 base of the Judith River beds on Dog Creek.' 



" Since the Coniornis type was collected some years prior to the 

 differentiation of these exposures into successive and distinct 



i Bull. No. 257, U. S. Geological Survey, 1905, p. 99. 



