THE LIVING ORGANISM 241 



temporary disturbances may be induced in 

 normal individuals, by excessive treatment 

 with sheep's thyroid glands. 



These results show, as Gley, a prominent 

 French observer on the subject, remarks, 

 that "the genesis and the exercise of the 

 highest faculties of man are conditioned 

 by the simple chemical action of a product 

 of secretion, a fact which should be borne in 

 mind by psychologists." 



The pituitary is a still smaller gland than 

 either suprarenals or thyroids, and is a single 

 gland attached to the base of the brain. Its 

 hypertrophy during youth leads to giantism, 

 and most giants exhibited at " shows," on 

 examination after death show hypertrophied 

 pituitaries. When the hypertrophy occurs after 

 growth of the skeleton is completed, the result 

 is a disease showing remarkable overgrowth of 

 certain bones only, known as acromegaly. The 

 overgrowth occurs chiefly in the bones of the 

 hands and feet, and the bones of the face, 

 especially the lower jaw, producing a remark- 

 able and unmistakable appearance. Giantism 

 is a somewhat rare disease, but cases in 

 elderly persons of the partial form are not so 

 infrequent. Small as the pituitary gland is, it 

 is composed of two parts of quite different 

 function. It is only the anterior portion 



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