652 



TITANOTHERES OP ANCIENT "WYOMING, DAKOTA, AND NEBRASKA 



hyognatJius by Osborn and Gregory only 19 dorso- 

 lumbars were assigned to this animal, but prob- 

 ably the last two dorsal vertebrae were missing in 

 the specimen upon which this restoration was based 

 (Am. Mus. 1843, figs. 579, 580). 



Without placing the specimens of D. Jiyognathus 

 and the more ancient D. longiceps side by side it is 

 difficult to determine from a comparison of the illus- 

 trations what are the really significant differences 

 between these two sets of vertebrae. In the D. lon- 

 giceps specimen the spine of the axis appears to be 

 more acute posteriorly, the spines of dorsals 6, 7, 8, 

 and of the posterior dorsals and lumbars seem to be 

 wider anteroposteriorly. 



Measurements of the skeletons of Dolichorhinus longiceps and 

 D. hyognathus, in millimeters 



Distance from tip of nasals 

 to last vertebra, as 

 mounted, on straight line; 

 right side 



Length of skull, pmx to eon- 

 d3'les 



Length of skull, nasal tip to 

 lambdoid crest 



Width of skull across zj'go- 

 mata 



P'-m' 



Mi-m' 



Pi-mg 



Lower jaw, incisors to angle. . 

 Length of neck as mounted-. 

 Scapula, length 



Humerus, length 



Radius, length 



Ulna, length 



Os innominatum, right, length 

 from crest of ilium to tu- 

 berosity of iscliium 



Number of dorsals 



Number of lumbars 



Number of sacrals 



Pield 

 Mus. 

 12200; 

 Uinta 

 B 1 



Carnegie 

 Mus. 

 2865 



1,910 

 533 



"570 



''210 

 184 

 122 

 195 

 423 

 360 

 375 

 275 

 287 

 330 



290 



17 



4 



4 



Am. Mus. 



1843; 



Uinta 



B2 



Am. Mus. 



13164; 

 Washakie 



337 

 285 

 295 

 340 



248 



C?)15- 



542 



580 



250 

 205 

 119 

 230 



420 



'308 



" Estimated. ' Modified by distortion. 



SUBFAMILIES TELMATHERIINAE, BRONTOPINAE?, AND 

 DIPLACODONTINAE 



Nothing was known of the skeleton of Uinta C 

 (true Uinta) titanotheres until the publication of the 

 memoir "The Mammalia of the Uinta formation," 

 by Scott and Osborn, in 1890 (Osborn, 1890.51). 

 Parts of four skeletons were described in this memoir — 

 Princeton Mus. 10393, 10395, 10396, 10396a. These 

 were all attributed to Diplacodon elatus. It is now 

 evident that this specific reference is somewhat 



doubtful, because, as we have already seen (p. 96), 

 Diplacodon elatus is only one of 

 four or five kinds of titano- 

 theres that were living contem- 

 poraneously during the period of 

 deposition of Uinta C. Since the 

 original Princeton expedition 

 the Princeton, American, and 

 Carnegie Museums have sent 

 parties into the same field, 

 which discovered parts of many 

 additional but very incomplete 

 skeletons. Unfortunately not 

 any of these skeletons are asso- 

 ciated with teeth or skulls in 

 such a manner as to enable us to 

 determine them specifically or 

 generically. It may be said, 

 therefore, that the skeletal char- 

 acters of the Uinta C titano- 

 theres are assigned only pro- 

 visionally. 



As there were no less than five 

 kinds of titanotheres in Uinta 

 C, such skeletal remains as are 

 found there may belong to any 

 one of the following phyla: (1) 

 Successors of the Telmatherium 

 phylum; (2) members of the 

 true Diplacodon phylum, in 

 which the skull is long and 

 Peterson. One-tenth natural slender, rescmbliug in some re- 

 spects that of the Menodontinae, 

 in others that of ancestors of Brontotherium; (3) 

 descendants and mem- 

 bers of the Manteoceras 

 phylum, so far as 

 known only in the 

 lower beds of Uinta 

 C; (4) members of 

 the Protitanoiherium 

 phylum, animals of 

 robust and large size, 

 skeleton progressive 

 upon that of Manteo- 

 ceras, believed to be 

 ancestral to Brontops 

 of the Oligocene; (5) 

 descendants or rela- 

 tives of EotitanotJie- 

 rium, a progressive 

 titanothere so far 

 loiown only from 

 Uinta B 2. 



With these precau- 

 tions clearly in mind, 

 I we may now describe the parts as provisionally referred. 



Figure 590. — Right fore 

 limb of Dolichorhinus 



Carnegie Mus. 2865. After 



Figure 591. — Manus of Dolicho- 

 rhinus longiceps? 



Carnegie Mus. 2865. Front view. After Peter- 

 son. One-third natural size. 



