422 • ON THE GREAT CHIMPANZEE. 



DESCRIPTION OF THE PLATES. 



PLATE LVIII. 



Side view of the skull of the adult male Chimpanzee {Troglodytes niger). 



PLATE LIX. 

 Front view of ditto. 



PLATE LX. 



Base view of ditto. 



PLATE LXI. 



Side view of the skull of the adult male Gorilla {Troglodytes Gorilla), wanting the 

 lower jaw, which is indicated in outline. 



PLATE LXIl. 

 Front view of ditto. 



PLATE LXIII. 



Base view of ditto. 



All the figures are of the natural size : the letters and numerals are explained in the 

 text, i beg to express my obligation to the skill and care of the accomplished artist, 

 Mr. Erxleben, for his important aid in the elucidation of the subjects of the present 

 memoir. 



