168 



SCIENCE 



[N. S. Vol. XLII. No. 1075 



more especially during embryonic and early 

 life, and ivhich also greatly affect the entire 

 metabolism, that of the nervous system in- 

 cluded, during adult life. I regard it as 

 not unlikely that with the growth of knowl- 

 edge of the chemistry of the animal organ- 

 ism we shall drop the term entirely. We 

 have already seen that the liver, according 

 to Claude Bernard's view, has an internal 

 secretion, yet this gland is not usually 

 classed with the endocrinous organs. In a 

 sense, too, as has been frequently pointed 

 out, every cell of the body furnishes in the 

 carbon dioxide which it eliminates a hor- 

 mone or product of internal secretion, since 

 under normal conditions the carbon dioxide 

 of the blood is one of the chief regulators 

 of the respiratory center, influencing this 

 center by virtue of its acidic properties. 

 These and other instances that could be 

 given show that the term internal secretion 

 could be greatly extended in its scope, but 

 in the present state of our knowledge it is 

 convenient to limit it to the products of a 

 certain number of glands. 



The generally accepted list of the organs 

 of internal secretion is as follows, though 

 even at this moment a foreign investigator-^ 

 is asking us to accept certain newly dis- 

 covered small structures located in the neck 

 as belonging to our list : the thyroid, para- 

 thyroid, thymus, hypophysis cerebri, epi- 

 physis cerebri, pancreas, mucosa of the 

 duodenum, the two adrenal systems (the 

 chromaphil tissue and the interrenal bodies) 

 and the gonads, or sex glands. 



Permit me to give you a few illustrations 

 of the derangement of health and bodily 

 structure that follow upon the removal or 

 disease of these glands. Many of you have 

 doubtless seen these illustrations, but I am 

 giving them here for the benefit of those 



25 ' ' Ueber eine neue Druse mit innerer Sekretion 

 (Grlandula insularis cervicalis)," N. Pende, Arch, 

 f. milcroscop. Anat., Vol. 86, p. 193, 1914. 



who have never been given proof of the 

 great significance of these glands in order 

 that they may have a background of fact 

 for the better apprehension of certain 

 chemical questions which I wish presently 

 to bring to your notice. 



The figure-'' is an illustration from a 

 well-known paper of the Viennese surgeon, 

 A. V. Biselsberg, in which he describes the 

 effects of removing the thyroid gland from 

 young goats. The two animals here shown 

 are of the same age and parentage. On the 

 twenty-first day after birth v. Eiselsberg 

 removed the thyroid gland from one of 

 them. The incision healed by primary in- 

 tention. After three weeks the control ani- 

 mal began to outgrow the one operated 

 upon and when four months old the animals 

 presented the appearance here shown. The 

 goat with thyroid removed has shortened 

 extremities, a shortened skull and an altered 

 pelvis due to a delayed ossification at the 

 epiphyseal line. The wool of this animal is 

 longer and easily torn out by the handful, 

 the sex glands are atrophied, the hypoph- 

 ysis is enlarged, the intelligence is low- 

 ered; in brief, a chronic pathological con- 

 dition is produced in this experiment which 

 finds an analogy in human beings and is 

 known as cachexia thyreopriva. We can 

 not enter into further details, but I may 

 remark that the results obtained in such 

 removal experiments vary greatly with the 

 age and with the species of animal used. 



In this figure we have the results of a sim- 

 ilar experiment which nature herself has 

 performed for us. The child here shown is 

 a thirteen-year-old idiotic myxedematous 

 dwarf whose general symptoms point to a 

 congenital absence of the thyroid gland. 

 Investigators have proved this to be the 

 true cause by anatomical studies of the 



26 The illustrations were shown in the lecture, 

 but can not here be reproduced. 



