616 MR. ST. GEORGE MIVART ON THE CRANIA__[Nov. 22, 
the bony palate back somewhat beyond the last molar teeth, and the 
very large size of the posterior palatine foramen, —also a defect of 
ossification in the palate on each side anterior to the palatine foramen 
(the openings being closed by membrane), the presence of an inter- 
parietal bone, and the great size of the premaxille, which join the 
nasals for one-third of the latter’s external margin. 
He also calls attention to the pointed and hooked character of the 
angle of the mandible, and to its very long and backwardly inclined 
coronoid process. In all these characters the British Museum skull 
agrees with the figure and description given by Dr. Peters, except 
that the palate is not quite so prolonged (the most anterior point of 
the hinder margin being on a line with the posterior edge of the last 
molars), and that there are two defects of ossification, instead of one, 
on each side of the palate; moreover, the condition of the sutures 
does not admit of perfect certainty as to the extent of the line of 
union between the zasa/s and premazille, which nevertheless appears 
to be about such as Dr. Peters describes. I may add that it agrees 
with Dr. Peters’s figure in the absence of a malar foramen, in the sharp 
production of the angle of the mandible backwards but not down- 
wards, and in the small extent of the projection of the premazille 
forwards beyond the incisors, or of the nasals above the anterior nares, 
so that the outline of the lateral boundary of this opening is not 
deeply concave when the skull is viewed laterally. 
The sphenoidal fissure and the foramen rotundum are represented 
by a single and very large opening. 
The anterior end of the inferior surface of the periotic developes a 
very marked process. 
As to the dentition, Dr. Peters’s remarks and delineations quite agree 
with the characters offered by the teeth of Dr. Gray’s Lepilemur 
murinus. For the anterior and internal pair of upper incisors are 
nearly double the size of the posterior and external pair, and both of 
one side are plainly visible when the skull is viewed laterally. The 
upper premolars have each but one large external cusp, and are about 
equal in vertical extent, the first premolar being at least equal, in 
this respect, to the second. The three upper molars have each two 
pretty equally developed external cusps, and a large antero-internal 
cusp, which is connected by an oblique ridge with the postero-external 
one*, and bounded internally, except in the last molar, by a cingulum. 
The postero-internal cusp is very rudimentary or absent. The greatest 
difference between any two contiguous upper grinding teeth is between 
the third premolar and the first molar, which is the largest. The last 
molar, which is the smallest of the three, is considerably larger than 
the last premolar. 
In the mandible the three premolars have also but one large exter- 
nal cusp each, the molars having each two such. The lower pre- 
molars slightly exceed in vertical extent the three molars, the first 
two of which (about equal in size) are quadricuspidate, while the fifth 
(the largest of the lower series of grinders) is distinctly quinquecuspid. 
* As noticed by Professor Huxley in Arctocebus: see antea, p. 822. 
