QUADRUMANA. 5 
The next step was to ascertain whether any special 
marks of resemblance would yield a further insight into 
the affinities of the fossil, and justify its reference to any 
of the genera of either family. <A difference in the shape 
of the hinder tubercle of the tooth, was first noticed in 
the recent Quadrumana. In the Semnopithecide it was 
large, but simple; im most of the Macacida it was par- 
tially subdivided into two cusps, the outer one being the 
largest. As this character was well marked in the fossil, 
it seemed decisive of its closer affinity to the Macacida ; 
and, as the smallest species in this family belong to the 
typical genus, I referred the fossil to the Macacus, and 
now propose to designate the extinct species represented 
by it ‘* Macacus cocanus,” the Eocene * Monkey or Ma- 
cacque. The portion of the fossil jaw is narrower from 
side to side, or more compressed, than in any of the ex- 
isting Macacques, and the internal wall of the socket of the 
tooth, in the fossil, is flatter and thinner. The ridge on 
the outer side of the alveolus, which forms the commence- 
ment of the anterior margin of the coronoid process, begins 
closer to the tooth. 
These characters establish the specific distinction of the 
extinct Macacque to which the fossil fragment of the jaw 
belonged, and afford additional proof, if such were wanting, 
that it could not have been accidentally introduced, in 
recent times, into the stratum out of which it was dis- 
interred. 
* Eocene, a term inyented by Mr. Lyell, from the Greek words 7#s, aurora, or 
the dawn, and xaos, recent, expressive of the lowest division of the tertiary 
strata, in which the extremely small proportion of fossil remains referrible to 
species yet living, indicates the first commencement, or dawn, of the existing 
state of the animal creation. 
+ A newspaper critic, when this discovery was first announced, suggested that 
the supposed fossil might be nothing more than the remains of some monkey 
belonging to a travelling menagerie, which had died, and been cast out in the 
progress through Suffolk. 
