2 SMITHSONIAX MISCELLANEOUS COLLECTIONS VOL. 63 



complete pelvis and articulated caudal series of 45 vertebrje con- 

 tinuing to the tip of the tail; Cat. No. 7957, U. S. Nat. Mus. Tw^o 

 tarsals of the distal row, four articulated metatarsals, a portion of 

 the fifth, and eleven phalanges. 



Localities. — Same as the type. 



Horizon. — From the upper part of an Upper Cretaceous formation 

 soon to be described by the U. S. Geological Survey, which includes 

 the equivalent of the Judith River formation and some older beds. 

 The fossiliferous horizon is also the equivalent of the upper part 

 of the Belly River formation, as described in neighboring areas of 

 Canada. 



Generic and specific characters. — Typically of small size. Skull 

 with facial portion much abbreviated, and deep vertically. Supra- 

 orbital horn cores small. Nasal horn core outgrowth from nasals, 

 large, slightly recurved, laterally compressed, and divided longitudi- 

 nally by median suture. Frill with comparatively sharp median 

 crest, fenestrse apparently of small size, and entirely within the 

 median element. Supratemporal fossae opening widely behind. Bor- 

 der of frill scalloped, but without separate marginal ossifications. 

 Dentition as compared with Triceratops greatly reduced. 



Description of skull. — The description to follow is devoted en- 

 tirely to a consideration of the skull, since it shows characters of 

 sufficient importance to readily distinguish it from all the other 

 known members of the Ceratopsian group, which in the greater num- 

 ber of instances have also been established upon cranial material. 



When found, the skull was entirely disarticulated, but the excel- 

 lent state of preservation of the bone and the absence of distortion 

 by crushing rendered the assembling of the scattered elements a 

 comparatively easy matter. This specimen is of the utmost impor- 

 tance in the evidence it gives for the proper interpretation of the 

 cranial elements, and especially the positive information it affords 

 relating to those parts of the Ceratopsian cranium now somewhat 

 in controversy. 



In the above diagnosis of the genus and species, it is stated to be 

 typically of small size. While this statement is true so far as 

 applied to the known specimens, it should also be stated that to 

 some extent the small size of these specimens may be due to the 

 immaturity of the individuals. The open sutures of the skull, 

 sacrum, and vertebra? all testify to the youth of the animals. 



Viewing the skull in profile (pi. i), one is especially impressed by 

 the great abbreviation of the facial portion, when compared with the 



