420 DR. C. F. SONNTAG ON THE ANATOMY, 



The suppressive agents are the various ductless glands. When 

 they are diseased the suppressive power is removed, the latent 

 power reasserts itself, and Man assumes certain ape-like 

 characters. Man, in fact, retains more foetal characters than the 

 Chimpanzee. The most distinctive character of the human 

 fcetus is the foot, for it has never been seen with the hallux 

 projecting from the postero-mesial aspect of the sole. 



The Chimpanzee differs from the white races of Man in its 

 pigmented, hairy skin, its thick lips, and its overgrown facial 

 skeleton, which exhibits large supra-orbital crests, prominent 

 zygomata and malar bones, prognathism and lai'ge mandible. 

 But diseases of the ductless glands cause Man to assume one or 

 more of these characters, for they remove the suppressive 

 agencies. In Addison's disease of the supra-renal capsules the 

 skin becomes pigmented ; and in the various disorders of the 

 pituitary body, so beautifully monographed by Cushing (15), the 

 lips thicken, the skull exhibits large crests, zygomata and malar 

 bones, maxillary or mandibular prognathism occurs, and there is 

 a variable amount of hirsuties. The extremities also become 

 large and clumsy. Many of these conditions are present as the 

 normal characteristics in the lower races of Man ; and one of the 

 most prominent features in the skull of Homo rhodesiensis is the 

 enormovis development of the supra-oi'bital crests. 



At a certain stage in development the foetuses of all Primates 

 have external genital folds. In the human foetus they continue 

 to develop and form the labia majora and mons veneris, and they 

 bury the labia minora and clitoris. In the lower Primates they 

 disappear and the clitoris is exposed on the surface. But the 

 Chimpanzee exhibits an intermediate condition. The mons 

 veneris is slight, and the labia majora ai^e represented by two 

 slight elevations of the skin over thickenings of the subcutaneous 

 tissue (PI. I. fig. C). The chief difference between the Chim- 

 panzee and Man is the absence of the hymen. In diseases of the 

 ductless glands the organs atrophy in Man. 



The biochemical reactions of the blood show that Man is 

 related to the Chimpanzee and other Anthropoids, and it is 

 evident from the above that the actions of the ductless glands 

 have altei-ed the appearances of these relatives in a pronounced 

 manner. Bolk (7) has shown that the suppressive action has not 

 only influenced the somatic features of Man, but it has retarded 

 his development and succeeding life phases. He believes that the 

 ancestor of Man changed his diet from frugivorous to omnivorous, 

 and the change may have been the factor which evoked the 

 suppressive action of the endocrine organs. 



The compressed head appears sunk between the shoulders, for 

 the neck is short. It is also more rigid than in Man. This 

 arrangement throws no obstacle in the way of the long arms, and 

 the shortness of the neck may be designed to give the powerful 

 levator anguli scapulae and levator claviculse a very sti-ong fixed 

 origin. 



