THE PROTEOLYTIC MECHANISM IN OPERATION 97 



ferments, are themselves called into being through a stimulus 

 to their mother cells sent out as a hormone messenger from the 

 digestive apparatus itself. 



"Similar cycles of co-ordination, however, are not unusual 

 in the organism. Indeed, the case just cited of the lymphocytes 

 developed in the lymph nodes through the action of the muscles, 

 and in turn serving presently to aid the muscles that indirectly 

 engendered them, furnishes us another and no less striking illus- 

 tration of such an harmonious dual alliance," 



HORMONES AND THE CORPUSCLE-BALANCE 



I shall not here discuss in detail the rationale of operation of 

 the remaining causes that are observed to promote leucocytosis. 

 which include cold baths on one hand and fevers of microbic 

 origin on the other ; contenting myself with the suggestion that 

 the cold bath stimulates the vasomotor apparatus of the sympa- 

 thetic system ; and that the bacterial toxins, when present in the 

 body fluids, doubtless stimulate the cytogenic apparatus directly, 

 while the bodies of the bacteria serve as a food pabulum for 

 the leucocytes that may lead to the proliferation of the latter 

 through cell division. 



The normal leucocytosis of pregnancy may also be dismissed 

 with the remark that it furnishes, in view of the known inva- 

 sion of the blood by foreign (placental) protein, strong cor- 

 roborative evidence for one phase of the Proteomorphic theory. 



It seems desirable, however, to speak a little more in detail 

 (though still very briefly) of the part in maintaining the cor- 

 puscular balance, and in determining the activities of the leuco- 

 cytes, that appears to be played by the endocrinous organs; in 

 particular by the adrenal bodies, the thyroid apparatus, and the 

 glands of the duodenum. 



To establish a strong a priori probability that some at least 

 of the internal secretions directly stimulate the activities of the 

 corpuscles, it is only necessary to appreciate the fact that the 

 corpuscles themselves must be classed among the important mem- 

 bers of the endocrinous system ; and to recall that the products 

 of the various ductless glands are observed to interact in mutual 

 stimulation and inhibition of the organs that produce them. 



When, therefore, to cite a specific instance, it is observed (as 

 in Cannon's experiments) that a sudden increase in the adrenal 

 secretions, induced by an emotional state of fear or anger, results 

 in an immediate increase of glycogen in the blood, in prepara- 

 tion for active muscular exertion, we may justifiably infer that 

 the increase has been brought about, in part at least, by stimulus 

 to the enzyme forming functions of the lymphocyte, induced by 



