SEMNOPITHECUS MAURUS- 
teeth are long, acuminate, triangular, slightly tending outward and twisted, with a 
deep longitudinal groove along the surface, that faces the opposite tooth, and an 
obsolete groove along the inner surface. Of the grinders, the second bicuspidate 
is somewhat larger than the first; they are both divided by a deep longitudinal 
groove, and the exterior point is considerably more prominent than the interior. 
The structure of the first and second of the quadricuspidate is perfectly uniform ; 
the crown is divided by a longitudinal and by a transverse groove, which constitute 
four elevated acute points : the third quadricuspidate differs from the others, in 
being terminated posteriorly by a very obscure ridge. Of the front teeth, in the 
lower jaw, the intermediate teeth are both longer and broader than the exterior 
teeth ; the latter have a slight curvature, and an obsolete heel at the base, which 
affords them a peculiar character. The canine teeth are shorter than the corre- 
sponding teeth in the upper jaw, nearly vertically disposed, slightly arched, rounded 
anteriorly, and obsoletely grooved posteriorly. The first grinder, which follows, has 
a structure essentially different from the first bicuspidate in man ; it is pyramidal, 
and terminates in a single point, which is very acute, and projects far beyond the 
regular series of grinders. The angular surfaces are unequal. The largest, which 
affords the most distinguishing character to this tooth, is situated anteriorly and 
exteriorly; it constitutes a very extensive oblique plane, which, in mastication, 
is applied to the broad interior surface of the canine tooth in the upper jaw : a 
smaller plane meets this from the opposite interior side of the tooth, and constitutes 
a sharp ridge, rising to the point of the tooth, which is somewhat obliquely trun- 
cated by a rough serrated edge : posteriorly, the tooth is defined by a smaller exterior 
and interior surface. The next tooth, which answers to the second bicuspidate, 
has generally the same form as the corresponding tooth in the upper jaw, but a small 
additional ridge exists posteriorly near the base of the crown. The first and second 
quadricuspidates agree with the corresponding teeth in the upper jaw, presenting 
individually four regular acute points; but the third lias an additional fifth point, at 
its posterior extremity, occupying nearly two-thirds of the breadth of the tooth, 
but, being above, less acute than the other points. It may be observed, that the 
grinders in the lower jaw are, upon the whole, narrower than these teeth in the 
upper jaw. 
I refer to the Plate of Illustrations annexed to this Number for an accurate 
view of the teeth as above described. In letters A. B. C. B. E. F. § G. all the 
details are carefully represented, and the separate parts are referred to in the Expla- 
nation of the Plate. My principal object has been to exhibit accurately the first 
grinder in the lower jaw, so as clearly to illustrate the description : it is represented 
therefore both in connexion with the general series, and separated from it. The 
