Exuiot Smitu, Sram of Archeocete. 43 
a Lizard greatly magnified. An anterior prismatic stalk (a), 
representing the pedunculi olfactorii, suddenly expands into a 
plump, broad, smooth mass (4), showing the form of the chief 
part of the cerebrum. The maximum breadth of the two hemi- 
spheres (fig. 1, 4) is 95 mm.; the greatest length of each (mea- 
Fic. 1.—Dorsal aspect of the natural cast described in the text. Two-ninths 
natural size. a@, olfactory peduncles; 46, cerebral hemisphere; , @, 
cerebellum ; ¢, é, fragments of skull. 
sured in front from the point where the ventral surface of the . 
olfactory peduncles appear to expand into the chief mass of 
the hemisphere) is 47 mm.; and the maximum depth is 54 
mm. Each cerebral hemisphere (exclusive of the olfactory 
peduncle) is slightly broader than it is long. 
The two olfactory peduncles are represented in the natural 
cast by a single prismatic process. This extends forward for a 
distance of 37 mm. (measured along the dorsal edge) in front 
of the point where the expansion to form the hemispheres com- 
