Page 453. 
506 ON GELADA RUEPPELLI. 
formed of two median triangular isosceles areas reversely directed, 
with their apices approximate, but separated by an interval 1:5 inch 
in length, of hair-covered skin. The base of the very obtuse-angled 
upper triangle, which is margined by black hair, is five and a half 
inches from the middle of the lower lip, and is situated opposite the 
larynx, its length being 3°75 inches, and its depth not being more than 
aninch. The lower triangle is also very obtuse-angled, with its base, 
slightly concave downwards, six inches long. 
Although the two nude triangles above described do not meet, they 
tend to form an hour-glass surface of florid skin, 7°75 inches along 
each lateral curve from horn to horn. The hair bordering it is an inch 
long or so and iron-grey in tint, from the almost’ equal admixture of 
black and white hairs. There is no carunculation of the skin in the 
nude spaces or at their borders. The pair of nipples are closely 
approximate, not being more than a quarter of an inch apart in the 
dried skin. They are situated in the nude area of the lower triangle, 
an inch above its base. 
In the female the general tint is a the same as that of the 
male; the hair is very much shorter and less faded at the tips. The 
interscapular hair is the longest, reaching nearly four inches, whilst 
that of the loins is not so black as in the male. 
The pectoral nude space is in the female carunculated all along its 
lateral and inferior borders. The two triangles which go to form it 
join apically by an isthmus 1°3 inch broad. The marginal hair is not 
mixed with white. The caruncles are numerous, and about a quarter 
of an inch in breadth, being ovate and flattened. The nipples are 
situated as in the male, and are an inch apart. 
In both sexes the face is nude below the line of the frontal 
eminences, and laterally from points a little less than half an inch 
outside the outer canthus of each eye, the nude spaces running straight 
downwards in the direction of the angles of the mouth, just before 
reaching which they turn and include the chin. 
The ischial callosities, which are subcircular, and a little less than 
two inches in diameter, are situated in a naked area which is carun- 
culated in the female. This area extends forwards for three and a 
quarter inches, broad opposite the mons veneris, which is therefore 
nude, the anterior border being non-carunculated, and gradually lost 
in the sparse hair of the abdomen. 
Osteological comparisons between Gelada and its allies are very 
attractive, but do not lead to very definite results. Those most im- 
portant in my estimation will be here recorded. 
The following are measurements of the larger bones in the 
male :— 
