1909. ] ANATOMY OF CERTAIN UNGULATA. 195 
also well known to occur in Sus. But in the specimen of 
S. eristatus which I examined the fissure did not reach the 
splenial on either side. It may be that this fissure is the real 
equivalent of what I have described above in Dicotyles as the 
corono-splenial junction. The fissure mentioned by Garrod as 
the equivalent of the latter does not, however, exist in my 
specimen. 
In any case it is clear that Babyrussa agrees with the Old World 
Pigs, and differs from Dicot yles, in the shorter and more obliquely 
running coronal fissures. 
The lateral fissure of Babyrussa is less oblique in direction than 
that of Sus, where the two furrows converge greatly anteriorly. 
There is a well-marked entolateral fissure, and indeed on the 
right side of one of my two specimens a second entolateral within 
the first. There is, furthermore, in Babyrussa as in Sus an 
ectolateral fissure, which is wanting—as is also the entolateral— 
in Phacocherus* and in Dicotyles. In both specimens of the brain 
of the Babyrussa which I possess the ectolateral fissure tends to 
be rather imperfect, being interrupted along its course by bridging 
convolutions, and is better developed anteriorly than posterior ly. 
Text-fig. 19. 
Brain of Babyrussa alfurus, lateral view. One-half natural size. 
s. Sylvian fissure. d. Suprasylvian. 
In Sus, on the other hand tf, the posterior part of this sulcus is 
the most clearly marked, as was the case on one side (the right) 
of one of the Babyrussa brains. It is to be noted that this 
ectolateral sulcus gives off many transverse branchlets in Baby- 
russé as in Sus; it is these small transverse furrows only which 
are visible in Dicotyles. 
The suprasylvian fissure is much like that of Sus; and I could 
see no variations of moment in the two brains of Labyrussa nor 
on the two sides of each brain. The fissure curves round 
posteriorly towards the ventral surface of the brain, this part 
corresponding, according to Garrod, with the descending limb of 
the same fissure in other Artiodactyles. I may remark that 
Babyrussa also agrees with the Wild Swine (Sus cristatus) in 
possessing a small descending limb of the infrasylvian in front of 
* Elliot Smith, Cat. Roy. Coll. Surgeons, f. ¢. fig. 182, p. 316. 
Owen, ‘The Anatomy of Vertebrates,’ vol. iii. 1868, p. 123, fig. 104. 
