Dr. H. Burmeister on Globiocephalus Grayi. 53 
vomer, much shorter. The narrow form of the anterior part 
of the intermaxillaries allows us to seé a considerable portion . 
of the maxillaries on all sides of the tip of the nose; these 
appear only as a narrow band in the European species. The 
form of the maxillaries, at their anterior extremity, is also 
different ;. they are here broader and shortly rounded, and 
nearly parallel on the outer margins. The orbital part is not 
so broad, and the hinder edge of the orbit not so prominent. 
On the other hand, the cerebral region of the skull is broader, 
and much more produced behind in my species. 7 
The small surface of the frontal bones seen behind the 
maxillaries is comparatively broader, and the elevated margin 
of the parietals which separates the upper surface of the skull 
from the occipital surface is nearly in a straight line, a little 
undulated on each side, but by no means curved forwards as 
in the European species. In the latter the exterior margins of 
the occipital surface, which are also the hinder margins of the 
Dacre groove, are inclined backward on both sides ; but they 
are perfectly parallel and much more prominent in G. Grayi, 
so that the general form of the occipital surface in this species 
is rather a plane than a portion of a spherical curve as in the 
European species. Hence the occipital condyles are more pro- 
minent posteriorly in the former and more retracted in the latter. 
Beneath, the general configuration of the skull is nearly the 
same in both species; but a very important difference is to be 
found in the length of the teeth-series. In the European 
species this series occupies only half the length of the margin 
of the maxillary, but in the new Argentine species nearly the 
whole margin, except only an extent of 2 inches at its hinder 
extremity. ‘This difference is very remarkable, and is due to 
the greater size of the teeth, especially the anterior ones. The 
European species has generally twelve teeth on each side, in 
some cases fourteen, or, exceptionally, only eleven. My new 
‘species has only nine teeth on each side in both jaws; and 
these are of nearly equal size, except that the first is somewhat 
smaller: in the European species, the first five teeth are very 
small, increasing somewhat in size posteriorly; and the seven 
following ones also are not equal in size, but gradually in- 
creasing. All the teeth in G. Gray are nearly of the same 
form, having a truncated molar surface and a very short pro- 
minent crown; more than two-thirds of each tooth is enclosed 
in the alveolus, terminating below in a conical root which is 
nearly closed, exhibiting only a very small opening in the 
middle (Pl. II. fig. 3, a tooth, half the natural size). 
~The lower jaw is rather strong. Each ramus is 21 inches in 
length, and 6 inches 4 lines.in depth at the well-marked. coro- 
