MALIGNANCY 31 



suggest certain paths of inquiry and experiment with the 

 view to discovering a cure. 



However much remains to be learnt of the glandular 

 system, it is known that the tissues respond or fail to re- 

 spond, and that characteristics are moulded in one way 

 or another, in accordance with the presence or absence, 

 the hypertrophy or atrophy, of these glands. When 

 sex is once determined the genital glands dominate 

 growth ; testes are more frequently correlated with larger, 

 ovaries with lesser, size. Ovariotomy allows undeveloped 

 male homologues greater opportunities ; early castration by 

 preventing differentiation preserves female characteristics. 

 If growth and size are mainly determined by the pituitary 

 and thyroid, emasculation appears to permit the pituitary 

 to exercise a greater influence on the legs, since the 

 eunuch's are longer than normal. Among the unsolved 

 problems of these organs is the phenomenon known as 

 unilateral acromegaly ; but the very fact that it occurs, and 

 that perfect symmetry is rare, shows how remarkably a 

 hormone, or regulators which Gley has named " harmo- 

 zones," can work or be inhibited. It seems that the 

 tissues are moulded according to the stimulation they 

 receive from secretions of which the chemical constitu- 

 tion may presently be as well known as that of adrenalin, 

 which exercises so powerful an influence on the blood- 

 pressure. A bone may be a function of many variables; 

 but one is a gland placed beside the brain. It seems prob- 

 able that the parathyroids influence the growth of nervous 

 tissue, since they control the irregular discharges of motor 

 nerves, and we yet learn that some forms of epilepsy are due 

 to hypo-parathyroidism. Thus not only growth, but much 

 normal behaviour, is ruled by what Bland-Sutton well calls 

 a glandular pantheon. That this is obviously so may 



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