GEOLOGICAL SUEVEY OF THE TERRITORIES. 331 



HOLCODUS, Gibbes, (Cope emend.) 



Yertebrse without the zygosphen articulation. Palatine bones llat, 

 horizontal alate ; its teeth not unequally exi^osed at the bases, or not 

 pleurodont. This genus bears the same relation as regards the palatine 

 bones and teeth to the genus Liodon that Clidastes does to Edestosau- 

 ms. 



HoLCODUS CORYPH^us, Cope, (Proc. Amer. Philos. Soc., 1871, De- 

 cember.) — A stouter species than the Edestosauri above noticed, with 

 an elevated occipital crest, rising vertically from the occipital condyle. 

 The upper jaw supports thirteen sharp, curved teeth, of which two arc 

 in the premaxillary bone. Palatine teeth, 12. Length, 30 feet. 



Found on Fossil Spring Caiion. 



HoLOODUS TECTULUS, Cope, {loG. clt.) — A smaller species than the last, 

 with the cervical vertebras flattened, and all the vertebrae with a rudi- 

 ment of the additional articulation found in Clidastes. Length, about 20 

 feet. Quadrate bone as in M. mudgei. 



From Butte Creek. 



HoLCODUS iCTERicus, Coi)e, Llodon ictericus, Cope, (Proc. Amer. 

 Philos. Soc, 1870, p. 577;) (Hayden's Geological Survey of Wyoming 

 and Adjoining Territories, 1871.) — In addition to the two individuals of 

 tuis species procured by Professor B. F. Mudge, in one of his geologi- 

 cal surveys, the writer obtained a considerable part of a third from a 

 low bluff on Fox Canon, south of Fort Wallace. It is a species of about 

 the size of the H. corypJiwus, and has a rather short head. It lacks the 

 rudimental zygosphene so prominent in H. corypliceus and H. tectulus. 



HoLCODUS MUDGEI, Copc ; Modon mudgei, Cope, (Proc. Am. 

 Philos. Soc, 1870, 581 ; Hayden's Survey Wyoming, &c., 1871, p. — .) 

 A specimen was obtained by Prof. Mudge, on the Smoky Hill Eiver, 

 jaws and with teeth were found on Fox Canon by the writer. The charac- 

 ters distinguishing it are the following: Vertebrae without rudimental 

 zygosphen; quadrate bones with plane surfaces from the proximal 

 articular surface and the external obtuse-angled ridge to the meatal 

 pit, the latter therefore not sunk in a depression as the other species. 



LIODOI^, Owen, (Cope emend.) 



Trans. Amer, Philos. Soc, 1870, p. 200. 



Yertebrae without zygosphen an d zygantrum. Palatine bones vertical, 

 separated from each other, narrowed ; the teeth more or less pleurodont. 

 Chevron-bones articulated freely with the caudal vertebrae. 



This genus embraces several species from the Kansas chalk, which 

 vary in size from that most usual in the last genus to the largest 

 known in the order. 



Liodon curtirostris, Cope, (Proc. Amer. Philos. Soc, 1871, De- 

 cember.) — The specimen above described was found by the writer on the 

 denuded foot of a bluff on the lower part of Fossil Spring CaQon. 

 The posterior part of the cranium, with several vertebrae, were found 

 exposed, and many other bones, including the cranium, were found only 

 covered by the superficial wasted material. Other portions were ex- 

 posed on excavating the blue-gray bed of the side of the spur adjoining. 

 The name has reference to the abbreviation of the head and jaws. These 

 are relatively shorter than in any other species here described where 

 these parts are known. The end of the muzzle does not overhang, but 

 descends gradually to the tooth-line. There are but 10 maxillary teeth 



