VII. Osteohgical Contributions to the Natural History of the Chimpanzees (Troglodytes) and Orangs (Pithecus). No. IV. Description of the Cranium of an Adult Male Gorilla from the River Danger, West Coast of Africa, indicative of a variety of the Great Chimpanzee (Troglodytes Gorilla), with Remarks on the Capacity of the Cranium and other characters shown by sections of the Skull, in the Orangs (Pithecus), Chimpanzees (Troglodytes), and in different varieties of the Human Race .