Section IV, 1919 [51] Trans. R.S.C. 



Preliminary Description of a Neiv Species of Trachodont . Dinosaur of 

 the Genus Kritosaurus. Kritosaurus incurvimanus . 



By Wm. a. Parks, Ph.D., F.R.S.C. 



(Read May Meeting, 1919.) 



In 1904, Mr. Barnum Brown, of the American Museum of Natural 

 History, found near Ojo Alamo, in New Mexico, the head of a tracho- 

 dont dinosaur which he described as Kritosaurus novajovius, gen. 

 et sp. nov.^ In 1914 Mr. Lawrence Lambe described a similar form 

 from the Belly River beds of Alberta as Gryposauriis notabilis, gen. 

 et sp. nov. 



Brown's genus is described in part as follows: "Skull deep; 

 muzzle narrow; frontals short, orbital portion reduced barely coming 

 to the border of the orbit; nasals and premaxillaries very long; quad- 

 rate elongate; quadrato-jugal short antero-posteriorly, completely 

 separating quadrate and jugal. Mandibular rami massive ; edentulous 

 portion decurved. Teeth spatulate in lower jaw." 



Lambe defines Gryposaurus as follows: "Skull large, narrow 

 and very deep, with highly arched nasals .... Quadrate high, 

 partially separated from the jugal by a small quadrato-jugal. Man- 

 dible robust. Predentary expanded laterally and deflected in its 

 hinder half, and posteriorly bifurcated below at the midline. Neural 

 spines of the anterior dorsal vertebrae long. Ischia not expanded 

 distally. Body covered with small, polygonal, non-imbricating, 

 tuberculate scales of rather uniform size."^ 



Some authorities consider these two genera to be identical; it is 

 not the purpose of this little article to discuss this question, but for 

 the present their identity may be accepted, and as Kritosaurus has 

 priority that generic name will be used. 



In 1918, an expedition of the Royal Ontario Museum of Palaeonto- 

 logy obtained the skeleton of a trachodont at a height of about 100 

 feet above the Red Deer river, in the bad lands of the Belly River 

 formation on Sand Hill creek. The specimen was lying on its right 

 side with the head, the ilium, and the diapophyses of the vertebrae 

 exposed. The premaxillary and predentary bones were destroyed, 

 and the extremity of the tail was later found to be absent. Work 

 done on the specimen since it was taken to Toronto shows that the 

 remainder of the skeleton is remarkably well preserved and that 



» Bull. Am. Mus. Nat. Hist., Vol. XXVIII, Art. 24, 1910. 

 2 Ottawa Naturalist, Vol. XXVII, Feb., 1914. 



