196 APPENDIX. 



as the one first found. The skull was wanting-, but many other parts of 

 the skeleton, including the vertebra? and the bones of the legs and feet, 

 were well preserved. Portions of five other individuals were found by 

 the writer on the same expedition. 



The most perfect specimen of this species yet discovered (number 

 1206) was obtained by Mr. T. H. Russell and the writer in October, 1872. 

 This skeleton was nearly complete when found, the skull, lower jaws, and 

 pelvis being especially well preserved. The locality was near that of the 

 type specimen. Another important skeleton (luxmber 1207) was found 

 in July, 1875, by Prof. B. F. Mudge, who was then in charge of one of 

 the writer's exploring parties. 



Other specimens of importance were obtained on subsequent expedi- 

 tions by Messrs. B. F. Mudge, S. W. Williston, E. W. Guild, Gr. P. 

 Cooper and H. A. Brous. 



These specimens, representing some forty different individuals, were 

 all found in essentially the same geolog-ical horizon of the middle Cretace- 

 ous. The localities are all in Western Kansas, and most of them near 

 the Smoky Hill Paver and its tributaries. 



The known remains of this species are all preserved in the Yale 

 College Museum. 



Hesperornis crassipes. Marsh. 



(Plates VII and XXVII.) 



Lestornis crassipes, Marsh. — American Journal Science (3), Vol. XI, p. 509, June, 

 1876. 



The type specimen of this species (number 1474) consists of a nearly 

 complete skeleton, found in the yellow chalk of western Kansas, by Mr. 

 Gr. P. Cooper, in April, 1876. These remains indicate a bird considerably 

 larger than the type of Hesperornis regalis, and one that may prove to be 

 generically distinct. The characters already mentioned, especially those 

 seen in the tarso-metatarsus, may possibly be merely sexual ; although it 

 would be strange indeed on this supposition, that no other specimens with 

 these features should have been found. 



In the present specimen, number 1474, the atlas is preserved, and is 

 represented in the cuts below. 



Figure 40. — Atlas of Hesptrornis crassipes, Marsh ; natural size. a. front view; I. side view; c. bottom view j 

 d. back view ; nc. neural canal. 



