382 EXAMPLES OF CHEMICAL CORRELATION 



that the complete analysis of the coordinate factors of our total metab- 

 olism would involve a survey, necessarily incomplete at the present 

 stage of our knowledge, of the whole gamut of physiological activities. 

 Without attempting to embark upon such an ambitious review, there 

 are certain outstanding factors in the regulation of metabolic activity 

 which compel our attention here, because the regulatory action which 

 they exert would appear to constitute the prime function of the tissues 

 concerned. 



FIG. 23. Cachexia strumipriva following total extirpation of thyroid; eleven years 

 after operation. (After Kocher.) 



The most striking effects upon the general metabolism of the body are 

 those which are exerted by the tissues of the Thyroid. Our attention 

 was first drawn to the importance of this gland in the bodily economy 

 by pathological conditions which are endemic in certain localities and 

 sporadic in all human communities. The disorders resulting from 

 improper functioning of the thyroid fall into two main classes, those 

 namely, which result from subnormal development or activity of the 

 gland, and those which result from its overactivity. 



The condition of Myxedema arises when the thyroid fails to develop 



