85 



humerus of a quadrumanous animal (Dryopithecus), equalling the 

 size of those bones in man, have been discovered by M. Fontan, 

 of Saint-Gaudens, in a marly bed of upper miocene age, forming 

 the base of the plateau on which that town is built. The molar 

 teeth present the type of grinding surface of those of the gibbons 

 (Hylobates), and as in that genus the second true molar is larger 

 than the first, not of equal size, as in the human subject and chim- 

 panzee. The premolars have a greater antero-posterior extent, 

 relatively, than in the chimpanzee; and in this respect agree more 

 with those in the siamang. The first premolar has the outer cusp 

 raised to double the height of that of the second ; its inner lobe 

 appears from M. Lartet's figure to be less developed than in the 

 gorilla, certainly less than in the chimpanzee. The posterior talon 

 of the second premolar is more developed, and consequently the 

 fore and aft extent of the tooth is greater than in the chimpanzee; 

 thereby the second premolar of Dryopithecus more resembles that 

 in Hylobates, and departs further from the human type. 



The canine, judging from the figures published by M. Lartet 1 , 

 seems to be less developed than in the male chimpanzee, gorilla, or 

 orang. In which character the fossil, if it belonged to a male, 

 makes a nearer approach to the human type; but it is one which 

 many of the inferior monkeys also exhibit, and is by no means to 

 be trusted as significant of true affinity, supposing even the sex of 

 the fossil to be known as being male. 



The shaft of the humerus, found with the jaw, is peculiarly 

 rounded, as it is in the gibbons and sloths, and offers none of those 

 angularities and ridges which make the same bone in the chim- 

 panzee and orang come so much nearer in shape to the humerus of 

 the human subject. The fore part of the jaw, as in the siamang, is 

 more nearly vertical than in the gorilla or chimpanzee, but whe- 

 ther the back part of the jaw may not have departed in a greater 

 degree from the human type than the fore part approaches it, as is 

 the case in the siamang, the state of the fossil does not allow of 

 determining. One significant character is, however, present, the 

 shape of the fore part of the coronoid process. It is slightly con- 

 vex forwards, which causes the angle it forms with the alveolar 

 border to be less open. The same character is present in the 

 gibbons. The fore part of the lower half of the coronoid process 

 in man is concave, as it is likewise in the gorilla and chimpanzee. 

 I am acquainted with this interesting fossil, referred to a genus 



1 Comptes Rendus de VAcademie des Sciences, Paris, Vol. XLIII. 



