1-50 THE THYROID, THE THYMUS, AND THE ADRENALS. 



tained from a transplanted thyroid brought into contact with 

 a raw surface prepared for its reception, through absorption 

 into the blood, not necessarily of a secretion at first, since the 

 glandular functions would then be in abeyance, but of the 

 glandular juices themselves, which have been found so remark- 

 ably active in cretinism, myxcedema, etc. 



We are brought nearer to the suprarenal glandular func- 

 tions when the symptoms usually referred to as "nervous" are 

 reviewed. The "muscular twitchings and tremors, spasms, and 

 even tetanic convulsions" remind us vividly of the stage of 

 stimulation of the adrenals, though they occur as results of 

 removal of the thyroid. That the functions of the thyroid 

 must be connected with the destruction of toxic elements of 

 internal origin is evident. Yet if its secretion enters the cir- 

 culation and enhances metabolic processes and oxidation, and 

 since it is not itself endowed with properties that enable it to 

 directly carry on such a process as stated, it can only do so 

 indirectly. In view of the data incorporated in previous chap- 

 ters, may the thyroid gland not supply the blood with some 

 agency through which, directly or indirectly, the suprarenal 

 glands are stimulated? 



Removal of the thyroid in rabbits and other herbivorous 

 mammals and birds is net followed by the above-mentioned 

 symptoms, whereas these are prominent in the carnivora: the 

 dog, cat, monkey, man, etc. Still, the so-called nervous dis- 

 turbances do not always occur in the latter: a fact which has 

 caused some authoritative physiologists Munk, of Berlin, for 

 instance to conclude that the thyroid was not an organ of 

 extreme importance to life. In his experiments 50 per cent, 

 of monkeys and rabbits and 25 per cent, of dogs and cats re- 

 mained unaffected notwithstanding the ascertained absence of 

 accessory organs. Cunningham, 9 in a series of very carefully 

 conducted experiments, also found that the ingestion of some 

 tissues thymus, muscle, etc. produced symptoms strikingly 

 similar to those observed in the thyroid intoxication, and con- 

 cluded that the latter cannot, therefore, be looked upon as 

 due to a specific derivative of the thyroid gland. Unlike Munk, 



9 Cunninghrm: Journal of Experimental Med., March, 1898. 



