MR. G. R. WATERHOUSE ON THE GENUS GALEOPITHECUS. 337 
the line between the anterior boundary of the orbits ; they are very narrow in front, and 
expanded posteriorly, the width at the base being more than double that of the apical 
portion. The intermaxillary bones are large, and approach to a quadrate form, the in- 
termaxillary suture being at right angles with the nasal bones. The palatal portion of 
the intermaxillary is'but of small extent, being encroached upon by the maxillaries. 
There are two large, oval, incisive foramina, the posterior boundary of which is formed 
by the bones last mentioned ; they are situated, however, almost wholly-in the inter- 
maxillaries. The palate presents an even and slightly concave surface. The palatine 
portion of the palate-bone has but a small antero-posterior diameter, being deeply emar- 
ginated posteriorly by two notches, in the form of two segments of a circle. The frontal 
bones articulate in front with the nasal, maxillary, and lachrymal bones ; they are pro- 
duced laterally, so as greatly to increase the depth of the orbits, and posteriorly into a 
large post-orbital process, which in some adult skulls is separated from the correspond- 
ing process of the malar bone by an interspace scarcely more than three lines in width. 
The lachrymal bones are large, and constitute the chief portion of the anterior boundary 
of the orbit ; they extend on to the face about 2 lines, and into the orbit about 34 lines. 
The lachrymal duct is large, and is situated within the orbit, but close to its anterior 
margin. 
The malar bone is of considerable extent, broad, and compressed, and forms an al- 
most horizontal platform for the eye to rest upon ; it is articulated anteriorly to the 
lachrymal bone, and internally to the maxillary ; posteriorly it assumes a nearly perpen- 
dicular position, and is bifurcated, the upper portion forming a post-orbital process, 
and the lower division being extended backwards, beneath the zygomatic process of the 
temporal bone, and enters into the composition of the glenoid cavity. The glenoid ca- 
vity is transverse, and very slightly concave from front to back ; the posterior descend- 
ing process is proportionately larger than in other Lemuride, whose skulls I have had 
an opportunity of examining, and differs in being decidedly recurved, so as partially to 
enclose the condyle of the lower jaw. The temporal ridges are well-marked ; they con- 
verge as they approach the occiput, but never meet, being separated by a space of sel- 
dom less than four lines. The occipito-parietal ridge is very marked ; the condyles are 
extensive and project, and between these and the large mastoid processes there is a deep 
depression, giving a singular irregularity to the occiput viewed posteriorly. The audi- 
tory bulle are small, but the mastoid portion of the temporal bone is inflated, and forms 
a large cellular cavity. The rami of the lower jaw diverge somewhat suddenly, and 
with a bold curve, from the symphysis menti ; the coronoid process is small, of a prismatic 
form, pointed, and almost perpendicular: the apex, however, is directed slightly out- 
wards and backwards ; this process has its origin about 2 lines behind the last molar 
tooth. The articular portion of the condyle is situated a little above the plane of the 
grinding surface of the molars, and about 2} lines behind the coronoid process. The 
VOL. II.—PART IV. 2yY 
