ADDENDUM 22Q 



apparently entirely without significance. Operative extirpations of the gland 

 in earliest childhood have, except in the single case of Komg previously 

 mentioned, furnished no symptoms of absence. However, we should not for- 

 get that we mostly deal with cases of resections and that also in most of the 

 cases statements as to the further course are absent. Then again we must 

 consider the presence in such cases of accessory lobules of the thymus. 



Just as little clarified appears to me the significance of thymic hyper- 

 plasia for pathology. In many cases only the significance of the mechanical 

 factors remain certain; this is however quite without significance for the ques- 

 tion of hyperthymization. For the rest we really only know that in a great 

 number of very diverse conditions we find thymus glands with supernormal 

 parenchymal values. Especially is this true for diseases of the ductless 

 glands. We find thymus hyperplasia very frequently in Basedow's disease, 

 apparently also in acromegaly, in hypophysial dystrophy, in myxedema, in 

 eunuchoidism, etc. It therefore occurs as well in conditions of glandular hyper- 

 function as 1 in hypo/unction. I believe, therefore, that we should exercise 

 great scepticism concerning theories that would explain the frequent 

 coincidence of Basedow's disease and thymic hyperplasia. On the same 

 ground I regard as at present quite hypothetical the correlations that 

 according to the views of many modern authors exist between the thymus 

 gland and the other glands of internal secretion. 



Also the experiments to produce hyperthymization artificially have up to 

 the present seemed scarcely satisfactory. The old experiments of Svehla are, 

 as has already been mentioned, not of value as evidence. The fewer ex- 

 periments of Hart with injection of powdered Basedow's thymus and those 

 of Bircher with implantation of Basedow's thymus in animals are worthy of 

 notice but do not furnish sufficient grounds for the support of a teaching of 

 hyperthymization. 1 Also the hypothesis that Wiesel provides at the end 

 of his unusually well-prepared work on the pathology of the thymus seems to 

 me on the face of it as still too little supported. Wiesel supposes that the 

 thymus gland furnishes to the blood path a secretion that acts vagotonically, 

 and he regards especially the eosinophilic cells present so abundantly in the 

 thymus gland as the seat of origin of this principle that acts antagonistically 

 to adrenalin. In this respect Wiesel identifies status thymicus and status 

 lymphaticus, although he does take pains to separate the two conditions 

 from each other in an anatomical sense. 



Addendum 



Boggs points out, without regards to the dulness due to enlarged thymus 

 is partially higher and more superficial than that due to diseased mediastinal 



1 Concerning the "thymogenic" Basedow's disease see chapter on thyroid gland, pp. 75 

 and go. 



