EOCERATOPS CANADENSIS, 
5 
to the front and toward the outer side. This bone met its fellow 
toward the front for a short distance in the midline of the skull. 
Outwardly on two of its sides it was bounded by the postfrontal. 
The suture for the nasal is shown in the specimen as a transverse 
groove in its front border. 
The frontal is not preserved, but its size and position are 
indicated by the inner posterior edge of the prefrontal (Plate IX, 
figure 1). It was, therefore, triangular in outline, and with its 
fellow, ran forward for some distance between the prefrontals. 
It appears to have been relatively smaller than the same bone in 
Centrosaurus (Plate IX, figure 2) and Styracosaurus and, 
as in these two genera, the posterior edge of the pair no doubt 
formed the anterior margin of the postfrontal fontanelle. 
The lachrymal is not preserved in the type material but it 
evidently formed the lower anterior part of the orbital rim, as a 
small roughened sutural surface (Plate I) at the lower limit of 
the postfrontal part of the rim, in line with the centre of the orbital 
opening, marks its entry into the formation of the rim. The 
lachrymal carries downward the prominence given to the rim 
by the postfrontal. Anterior to this small roughened surface 
the remainder of the lachrymo-postfrontal suture is not clearly 
indicated. From our knowledge, however, of the exact shape 
and position of the lachrymal in Centrosaurus it is probable that 
this bone in Eoceratops would have somewhat similar propor- 
tions and lie along the lower edge of the postfrontal reaching 
the nasal in front. 
The nasal (Plate I) is short, very deep, and thin through 
from the exterior to the interior surface. Interiorly in front a 
narrow, stout process descends to articulate with the premaxilla, 
and posteriorly there is a broad thin extension passing down- 
ward to meet the posterior ascending process of the premaxilla. 
Between these processes the lower border is deeply emarginate 
and forms the upper half of the nasal opening. The outer 
surface is flatly convex from above downward. The bone thins 
near the hinder border and flares outward to form a suture 
overlapping the lachrymal and postfrontal, and fitting into the 
grooved anterior edge of the prefontal. 
