ON BRITISH FOSSIL MAMMALIA. 55 



Order Quadkumana. 

 Genus Macacus. 



The existence of this genus during the earlier tertiary epochs was esta- 

 blished by the discovery, in sand, beneath a stratum of blue clay, at Kyson 

 near Woodbridge, Suffolk, of a fragment of a lower jaw, including the socket 

 of the last molar, with that highly characteristic tooth entire and in place, 

 and the anterior part of the base of the coronoid process. This fossil was 

 determined by me in August 1839* ; it was of a dark colour and brittle 

 from the loss of its original animal matter, but less absorbent than the cave 

 fossils usually are. The crown of the tooth presents five tubercles, the four 

 anterior ones being arranged in two transverse pairs, the fifth forming the 

 posterior heel or talon. This conformation of the crown of the last molar of 

 the lower jaw, is characteristic, as is well known, of two families of catarrhine 

 or old-world monkeys,— the Semnopithecidce, including Semnopithecus and 

 Colobus, and the Macacidce including Macacus, Cynocephalus and Papio. 

 In the Semnopithecidce the fifth tubercle or talon is large but simple. In 

 most of the Macacidce it presents two cusps, the outer one being much 

 larger than the inner one. This character is well marked in the fossil, and 

 reduces it to the lower group, or Macacidce; in which, after a close com- 

 parison with several recent species, it appears to me to come nearest to the 

 true Macaci. But the fossil exhibits the following differences from the re- 

 cent Macaci : — the whole tooth is rather narrower in proportion to its length ; 

 the transverse ridge at the anterior part of the tooth crossing the base of the 

 two anterior tubercles is a little more prominent, and passes more obliquely 

 from the outer to the inner side ; the second transverse ridge uniting the 

 first pair of tubercles, rises nearer to their summits ; the portion of the jaw 

 is more compressed than the corresponding part of the jaw in the recent 

 Macaci; the internal wall of the socket of the tooth is flatter and much 

 thinner ; the ridge on the outer side of the alveolus, which forms the com- 

 mencement of the anterior margin of the coronoid process, begins closer to 

 the tooth. These characters are sufficiently important and well-marked to 

 establish the specific distinctions of the Macacque to which the portion of 

 the jaw belongs, and are the more valuable as corroborating the evidence 

 already adduced in proof that the fragment in question is a true fossil of the 

 Eocene stratum in which it wus discoveredf. 



A second specimen of the fossil Macacus consists of the crown and one 

 fang of the second molar, left side, lower jaw ; or the tooth which corre- 

 sponds with the second ' bicuspis ' in human anatomy ; it was discovered in 

 the same stratum and locality as the preceding. The crown presents four 

 tubercles arranged in two transverse pairs, the anterior pair being the most 

 distinctly developed, and rising the highest ; there is also a very small ridge 

 at the anterior, and another at the posterior side of the crown ; the latter is 

 placed between and connects together the two posterior tubercles. The 

 fangs are two, strong and divergent ; the anterior one has been broken off. 

 The grinding surface of the tooth presents two depressions, a small one in 

 front of the anterior pair of tubercles, and a larger one between the two pairs 

 of tubercles. The tooth has evidently belonged to an old individual, for the 

 tubercles are worn, and the posterior concavity is smoothed and deepened 

 by attrition. It differs from the corresponding tooth of a recent Macacus 



* See Magazine of Natural History, 1839, p. 444. 



t A newspaper critic, when this discover}' was first announced, suggested that the sup- 

 posed 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. 



