ENDOCRINE GLANDS AND THEIR FUNCTIONS 



673 



suits in the production of giants or dwarfs. A decreased supply 

 of the hormone in an immature individual, if the condition is not 

 remedied by administration of the hormonal extract, retards the 

 growth of the body and may cause a complete cessation of growth. 

 The dwarfs of the circus furnish examples of this unfortunate con- 

 dition, although not all dwarfism must be thought due to this cause. 

 For example, the cretin described previously is the result of thyroid 

 disorder and is usually a mental dwarf as well as a dwarf in body, 

 while dwarfism resulting from deficient phyrone is accompanied in 

 most cases by a normal mental development. 



Fig. 363. — A pituitary dwarf at the age of nine and one-half years, compared 

 with a normal child of the same age. (From Zoethout, Textbook of Physiology, 

 after Engelbach.) 



An overfunctional anterior pituitary results is a marked increase 

 in the growth of bones, although the general development of the 

 individual thus affected may be symmetrical and the physiological 

 processes may be normal in every respect. Cases of this type are 

 commonly seen. One such instance may be cited in which a nine- 

 year-old boy measured six feet and one inch and weighed 178 pounds. 

 His mental condition was normal. 



Another condition, known as acromegaly, may result from an over- 

 functional anterior lobe of the pituitary during adult years. The 



