142 THE POPULAR SCIENCE MONTHLY 



DUCTLESS GLANDS, INTERNAL SECRETIONS AND 

 HORMONIC EQUILIBRIUM. Ill 



Br FIELDING H. GARRISON, M.D. 



WASHINGTON, D. C. 



IV 



THE most remarkable fact about the internal secretions is that they 

 are correlated with one another. Not only has this been abun- 

 dantly demonstrated by experiment, but, in many cases, pathological le- 

 sions of the individual glands cause some disturbance in the functional 

 relations of the other glands — the so-called "pluriglandular syndromes." 

 The idea of a correlative relation is not necessarily new, was perhaps 

 implicit even in Bordeu's statement of the theory, but it did not begin 

 to acquire tangible and intelligible form until the complex chemistry of 

 the metabolism of the body had beeen better understood. On the 

 physiological side, it has been noted, for instance, that excision of the 

 pancreas produces glycosuria, even after thyroidectomy and parathyroid- 

 ectomy, but not after excision of the adrenal bodies; that partial exci- 

 sion of the thyroid in bitches will produce a mild myxoedema, if 

 pregnancy supervenes, the symptoms disappearing after littering; that 

 the thymus gland is often enlarged in exophthalmic goiter but will 

 atrophy after thyroidectomy ; that castration is followed by enlargement 

 of the thymus, and, conversely, excision of the thymus produces swell- 

 ing of the ovaries. On the pathological side, the thyroid is often en- 

 larged during puberty, menstruation, excessive venery (e. g., in prosti- 

 tutes) and pregnancy; swelling of the ovary and menstrual disturbances 

 often accompany goiter. Myxoedema often comes on at the menopause 

 or in connection with sterility. Acromegaly, as was shown by Edwin 

 Klebs, is often accompanied by enlargement of the thymus. Enlarge- 

 ment of the pituitary often accompanies pregnancy or hibernation, yet 

 castration causes enlargement of the pituitary in the young and acrome- 

 galy is often associated with loss of sexual power. The fact that many 

 of these experimental results and pathological findings do not harmonize 

 makes the problem one of extreme complexity. Furthermore, it is 

 known that lesions of different ductless glands will produce isolated 

 identical effects, which overlap each other in a group of symptoms, 

 making the causal relation dubious when there is a "pluriglandular 

 syndrome." Glycosuria (lowered tolerance for carbohydrates) may be 

 produced by goiter, by injection of thyroid extract in acromegaly or by 

 injection of pituitary extract, by excision of the parathyroid body, by 



