1914] The Ottawa Naturalist. 131 



Measurements. [Continued] Feet. Inches. 



Lengdi of metacarpal III 3f 



IV 2h 



" tirst phalanx of digit II 3f 



" terminal " " " 3 J 



" first HI 21 



" seconel " " " 3| 



" scapula and coraeoid together 3 6 



Carpal bone with diameter of J 



" length " 



Two carpal bones with length each of 0| 



Protorosaurus, gen. nov. 



Skull large, broadly triangular in superior aspect, with an 

 abbreviated facial portion and a greatly expanded posterior 

 crest ending squarely behind. Coalesced parietals forming a 

 slender frame-work enclosing large subtriangular fontanelles. 

 Squamosals very long and narrow with a scalloped free border. 

 Epoccipitals present. Supraorbital horn-core small, upright. 

 Orbit small. Supratemporal fossae not greatly developed. Body 

 covered with non-imbricating plate-like, and tubercle-like scales. 



This genus is proposed for the reception of the Belly River 

 Cretaceous ceratopsian species originally described by the writer 

 under the name Monoclonius belli. 



The species was established in 1902* on a large portion of 

 the coalesced parietals discovered by the writer in 1898 in the 

 Belly River formation on Red Deer river, Alberta, below the 

 mouth of Berry creek (Steve ville). In the original description 

 the opinion was expressed that the species represented was 

 "probably ancestral to such later forms as Torosaurus latus and 

 T. gladius of Marsh, from the Laramie of Wyoming." This 

 belief is strengthened by the discovery during the past summer 

 of a skull, with most of the skeleton, of one individual of this 

 species at the type locality. It is now evident that this Belly 

 River form is generically distinct from both Monoclonius, Cope 

 and Ceratops, Marsh, and that its affinites are with Torosaurus, 

 Marsh, to which it apparentlv leads in a direct line of descent, 

 and from which it differs by well-marked primitive characters 



The characters in Protorosaurus which are regarded as 

 primitive in comparison with Torosaurus are its smaller size, 

 the greater relative length of the skull in front of the orbits, the 

 retention of the scalloped free margin in the squamosal, the 

 greater size of the intraparietal fontanelles which have been 



* Contributions to Canaiian Palaeontology, vol. i i (quarto), pi. ii, On vertebrata of the 

 mid-cretaceous of the North-west Territory, 2. X ra and species from the Belly 



River series, p 66. pi. xx. fi??s 1 and 2. 



