244 HUMAN BIOLOGY 



"infant Hercules" type. In woman such tumors have the 

 extraordinary effect of giving the female some of the male 

 characters, e.g. a deep voice and a beard, and removing a 

 number of the typical features of the female. 



The endocrine glands which especially influence growth 

 are the thyroid and the pituitary which is at the base of the 

 brain. If the thyroid is deficient from birth the condition 

 of cretinism results. Unless treated the child remains a 

 dwarf, hideous in appearance, and furthermore an idiot. 

 Such monsters are now rare, for it is commonly known that 

 by giving a preparation of the thyroid gland it is possible 

 to bring about a natural development of body stature 

 and of the nervous system. The transformations thus 

 wrought seem nothing short of miraculous. If there is 

 deficiency of the front part of the pituitary gland, dwarfism 

 results, but the dwarf is not idiotic. He is unusually fat, 

 especially about the hips, he has an infantile body form, 

 and there is failure of development of the reproductive 

 organs. When this portion of the pituitary gland is over- 

 developed and overactive in youth, growth, especially of 

 the long bones, is excessive. The result is a giant. The 

 large growth of the pituitary body enlarges the bony pocket 

 in which it rests, and with the x-rays it is possible to see 

 in the skulls of living giants the evidence of the cause of their 

 abnormality. Recent experiments indicate that the growth- 

 principle of this gland has been isolated and can be used 

 eff^ectively in promoting growth during adolescence. 



The foregoing references to the functions of the endocrine 

 glands should be regarded as merely illustrative. In each 

 instance it is clear that an organ in one part of the body 

 has remote effects on parts far removed from it. The connect- 

 ing agency is not the nervous system, but the other great 

 integrating system of the organism, the circulating blood 

 and tissue fluids. 



REFERENCES 



Bainbridge, F. a. 1923. The Physiology of Muscular Exercise. Ed. 2, Lond., 

 Longmans, Green. 



Cannon, W. B. 1926. Some general features of endocrine influence on metab- 

 olism. Am. J. Med. Sc, 171: 1-20. 



