52 THE ROYAL SOCIETY OF CANADA 



the animal had been very quickly entombed, as a thickness of nearly 

 two feet of rock lies between the ribs of the right and left sides, and 

 the two sternal bones remain in their natural position at a high angle 

 to each other. As the upper or left side has been somewhat affected 

 by weathering, it has been decided to prepare the specimen as a panel 

 mount, showing the under or right side. Preparatory to doing this 

 the left shoulder girdle and fore limb have been removed; they reveal 

 an unusual structure, particularly of the manus, which seems to justify 

 a preliminary account which must be of some generic value even if 

 the species is not new. 



The Head 



Figure 1. 



The head shows conclusively that the specimen belongs to the 

 genus Kritosaurus, an opinion which has been confirmed by Mr. 

 Brown after the examination of photographs. The resemblance of 

 our specimen to Lambe's Gryposaurus notabilis is very striking 

 and it may yet prove to be another example of that species. There 

 are, however, some points of difference which, in my opinion, are 

 sufficiently marked to justify the creation of a new species. In the 

 first place, the highly arched nasals, so characteristic of Gryposaurus 

 notabilis, are not to be seen in our specimen. In Lambe's figure, a 

 vertical line drawn from the anterior end of the lachrymal passes 

 through the summit of the nasal prominence; a similar line in the new 

 specimen cuts the superior aspect of the nasal at a point scarcely 

 above the preorbital level. In the second place, the distinct emargin- 

 ation of the anterior border of the orbit, on which Lambe places especial 

 stress in his description of Gryposaurus notabilis, is not seen in the 

 specimen under examination. Other points of difference of less signifi- 

 cance are the smaller size of the head, the more quadrangular form of 

 the orbit, and the inward deflection of the proximal end of the mandible 

 (possibly due to pressure). 



The general anatomy of the head corresponds so closely to that 

 of Gryposaurus notabilis that a further description is unnecessary 

 here. The following measurements will serve to illustrate the general 

 similarity but smaller size of the new species : 



