206 



. Quadrumana. In the structure and development of these bones, the 

 Chimpanzee resembles man much more nearly than the Gorilla. 



4. Palate bones. — The hard palate is more quadrangular and 

 narrowest in the Gorilla ; the palate bones are shorter from before 

 backwards, and are emarginated in the middle line ; in the Chimpan- 

 zee, as in man, these bones have no notch in the middle of the hinder 

 edge, but in the place of it form a slight projection backwards. 



5. Teeth. — The incisors of the Chimpanzee are relatively the largest, 

 but, being flatter and more chisel-shaped, have a closer likeness to those 

 of man. The canines were not protruded. The outer cusp of the first 

 upper molar is much longer than the inner, forms a nearly equilateral 

 triangle, and has a small conical projection Justin front of, as well as be- 

 hind its base. In the Chimpanzee the outer cusp of the same tooth is 

 scarcely more prominent than the inner, and the whole tooth agrees 

 very nearly in shape with the corresponding one in a child. The first 

 molar below (dm, 1) is remarkable for its conical form, resembhng in 

 its bluntness and general structure one of the premolars of a hyaena. 

 It is a little compressed from side to side, has a slight ridge before and 

 behind, and a small tubercle at the base of it. There is an irregular 

 triangular indentation on the inner face of the crown. 



In the Chimpanzee, the principal cusp is relatively smaller ; occupies 

 only two-thirds of the crown, and on the inner side of it is a second 

 cusp ; behind these cusps is a large fossa, and behind this another 

 small cusp. 



In neither the Chimpanzee nor the Gorilla do the teeth just described 

 resemble in type those of a child ; but if complication of surface can 

 be considered as at aU characteristic, the teeth of the former are more 

 human than those of the latter ; the principal cusp of the Gorilla 

 covering a much larger portion of the crown, in addition to being 

 relatively much longer. 



The following letters were read, which had been recently- 

 received, viz . : — 



From the Naturforschende Gesellschaft, Emden, February 19th, 1862 ; 

 the Smithsonian Institution, March 18th, 1862; the California Acade- 

 my of Natural Sciences, November 1st, 1862 ; and from the Royal 

 Horticultural Society, London, Dec. 10th, 1862, acknowledging the 

 receipt of the Society's publications. From the K. K. Akademie der 

 Wissenschaften, Wien, August 1st, 1862, and the K. Preussische Aka- 

 demie, October 15th, 1862, presenting their publications. 



Temple Prime, Esq., of New York, was elected Corres- 

 ponding Member. 



