68 ROY L. MOODIE 
clearly marked that it seems worthy of description. The presence of 
horns as given in the restoration of the skull is based on the analogy 
with the other two species of this genus in both of which horns are 
present. The generic determination of the species is based on the 
large size of the postorbital which is essentially characteristic of the 
other species of Diceratosaurus. 
The characters which distinguish the species from the others of the 
genus are the large postorbitals and the small parietals which are 
excluded from union with 
the postfrontals on account 
of the large ‘size volte 
frontal. In the other two 
known species the frontal 
is small and the parietal 
comes forward to join the 
postfrontal. ‘The present 
species exhibits a skullly 
which is nearly twice as 
large as that of D. laevis 
and nearly three times the 
size. of othe =skullon aa) 
punctolineatus. 
Fic. 15.—The skull of Diceratosaurus ro- The portion of the skull 
bustus. E=epiotic; F’—frontal; J =jugal; ae preserve d shows the 
postfrontal; P=parietal; Po=postorbital; Qj= , 
quadratojugal; So=supraoccipital; Sq =squa- cranium to have had a 
mosal. rather acuminate snout, not 
blunt as in the type species. 
The orbit is an elongate oval although it has the same relative position 
in the skull as in the other species. The nostril is indicated by an oval 
depression near the anterior edge of the skull. The frontals as indi- 
cated by the sutures present on the portion of the skull preserved are 
fully as long as the parietals. Whether they were as wide as is 
represented in the drawing (Fig. 15) is uncertain. The postfrontals 
are represented by very small bones the sutures of which are somewhat 
uncertain although they cannot be far from what is represented in the 
drawing. ‘The postorbital is large and elongate. It is distinctive 
of this species on account of its unusual size and of the genus as well, 
