346 HENEY D. JUMP 



ous glands. We refer to the thymus, anterior pituitary body, pineal body, 

 suprarenal body and the gonads. They may act as accelerators or in- 

 hibitors. 



If one be acceleratory we should look for a hyperplasia and increase 

 of function in it at the time of puberty: stimulation of it as by a cer- 

 tain class of tumors should cause precocity: ablation should delay develop- 

 ment ; feeding or transplantation of the gland from young animals should 

 cause precocity. 



If one be inhibitory we should find it atrophying at puberty: a de- 

 structive tumor in it or ablation of it should hasten puberty ; feeding of 

 the gland should delay puberty. 



In none of the glands are all of these conditions fulfilled. In some 

 a part are, in others the testimony is conflicting. From the evidence avail- 

 able we are warranted in believing that all of these mentioned have an 

 influence upon the development of these characteristics and of believing 

 that there is probably a relation or correlation of function in them all. 



Alterations therefore in the functions of the glands governing the 

 normal development of puberty should be looked for in cases of abnormal 

 development. Such alterations have been found in reported cases in the 

 pineal body, anterior pituitary body, suprarenals, and gonads. 



The evidence has been clinical, associated with the pathological find- 

 ings in those cases of precocity which came to autopsy, and experimental: 

 ablation of glands and feeding to young animals the raw glands or the 

 desiccated preparation of them, taken from young animals. It is unfor- 

 tunate that, in some of the cases in which autopsies were done, the asso- 

 ciated ductless glands were not examined. 



Thymus 



This gland shows signs of involution at the time of puberty. Accord- 

 ing to Waldeyer and Ilammar it grows up to the age of puberty and then 

 loses weight but continues to functionate in less intensity even into old 

 age. Calzolari found that in castrated male rabbits the thymus atrophies 

 more slowly than normally. Xormal involution would seem to depend on 

 the development of the sexual organs. Marine and Manley experimentally 

 removed the thymus from young animals and saw a hastening of sexual 

 maturity in them. On the other hand E. A. Park could detect no changes 

 in the procreative functions of thymectomized guinea pigs. Hewer fed 

 thymus to young male white rats and found a delay in the development of 

 the testes. When the gland was fed to adult rats a degeneration of the 

 testes followed. There are no reports on the condition of the thymus in 

 cases of precocious puberty. It would seem, however, that we are justified 

 in believing that this gland has an inhibiting effect upon sexual develop- 

 ment. 



