X.—On Two New Gorilla Foetuses

Synopsis Descriptions are offered of two foetal gorillas representative of developmental stages intermediate between those previously described by Duckworth (1904), Schultz (1927) and Deniker (1885). They are numbered accordingly II and IV and comparison made throughout with the other stages represented in the literature. Special attention has been paid to the ontogenetic changes occurring in the bodily form, and posture, cutaneous structures, cranial and skeletal development and in the disposition of the thoracic and abdominal viscera, much of which is previously known only in respect of Deniker's stage V.