OSTEOLOGY OF CAKNIVOROUS DINOSAUES. 123 



ments representing a considerable portion of a skeleton." Collected hy J. B. 

 Hatcher, 1888. 



Type locality. — Near the mouth and on the east side of Cow Creek, Fergus 

 County, Montana. 



Horizon. — Eagle sandstone. Upper Cretaceous. 



The brief original descrijition by Marsh is as follows: 

 A third species much larger may be called Ornilhomimus grandis. The third metatarsal was about 

 600 mm. in length, and its distal end 90 mm, in transverse diameter, and SO mm. in antero-posterior 

 diameter. 



It would appear that the type specimen should be in the United States National 

 Museum collections, but after a search extending over a period of several years 

 I have been unable to locate it. Portions of two other individuals referred to this 

 genus and species by Marsh are Nos. 2110 and 6183, U.S.N.M., both from the 

 Lance formation of Niobrara County, Wyoming. Of these Marsh says: 



Portions of two other skeletons have since been obtained, wliich apparently pertain to this species. 

 In one [No. 6183, U.S.N.M.] of these the femur, tibia, and fibula are in good preservation, and they 

 clearly demonstrate that this reptile was one of the largest of the Theropoda. The femur and tibia have 

 each a very large cavity in the shaft, with well-defined walls. Even the fibula has a ca\-ity in its upper 

 portion. In the other specimen [No, 2110, U,S.N,M,] the second metatarsal is in fair preservation 

 and shows the same form as in the type of the genus. 



Both of these specimens are here referred to the genus Tyrannosaurus, and 

 in all probability the type of 0. grandis when found will also be referable to a genus 

 distinct from Ornithomimus. Osborn ' has suggested "it may belong to the genus 

 Deinodon Leidy, but until the typo is located, it must remain of doubtful position 

 as regards its generic affinities." 



DEINODON, species. 



Deinodonl Gilmore, C. W,, Prof, Paper, U, S. Geol. Surv., 98-Q, 1910, pp. 287-288, pi, 73, figs. 

 1 and 4. 



The following specimens in the United States National Museum are provision- 

 ally identified as pertaining to the genus Deinodon. 



Specimen No. 8346, U.S.N.M., consisting of the greater portion of a left dentary,^ 

 collected bj^ J. B. Reeside, jr., "28 miles south of San Juan River and about 12 

 miles east of the Navajo Reservation line at the head of Hunter, Wash," from the 

 upper jjart of the Kirkland Shale, in 1915. 



In this bone there are alveoli for 13 large teeth, but excepting a germ tooth 

 in the ninth alveolusjrom the front all the others have been lost. This germ tooth 

 is compressed laterally, lenticular in section in the upjier portion and serrate on 

 both borders. The 13 alveoli occupy a space about 354 millimeters long. At 

 the third alveolus the dentary on the external side has a depth of 93 millimeters; 

 at the eleventh alveolus it is 110 millimeters deep. As in other Cretaceous Thero- 

 poda, the alveolai' partitions expand internally into interdental rugosae. In the 

 number of tooth sockets this jaw agrees with Dynamosaurus imperosus Osborn, 

 but in the general form of the dentary, particularly the contour of' the anterior 



1 Bull. Amer, Mus. Nat. Hist., vol. 35, p. 740, 1917. 

 . ! Prot. Paper 98 Q, U. S. Geol. Surv., p. 288, pi. 73, flg, 1, 1916. 



