THE SYMPATHETIC SYSTEM 119 



2. ACTION ON GENERAL NUTRITION. It is parallel to 

 the preceding. After the removal of the thymus the weight 

 curve decreases slowly in comparison to that of controls. 



3. ACTION OF THE GENITAL GLANDS. The develop- 

 ment of the ovary and testicle shows a marked delay 

 after the removal of this gland. It seems as if there was 

 a balance between the thymus and the genital organs and 

 that the thymic involution begins at puberty at the time 

 when the genital glands become active. 1 In the castrated 

 male animals, the thymus atrophies much later than in 

 controls (Cazolari). 



4. ACTION ON THE BLOOD PRESSURE. Extracts of 

 thymus taken from children or animals, injected intra- 

 venously cause a marked drop in the arterial pressure. 

 This hypotensive action which also belongs to the extract 

 of lymph glands, should not be looked on as the result of 

 an internal secretion. In athrepsia, atrophy of the gland 

 goes hand in hand with a decrease with its hypotensive 

 properties (Lucien and Parisot). 



When all is said, there probably is an internal secretion 

 to the thymus, although we do not know of any specific 

 substance in this gland; its constituents have not the 

 appearance of a glandular epithelium, and the clinical 

 suppression of the thymus does not cause a clinical syn- 

 drome comparable to the removal 'of the thyroid or 

 the parathyroids. 



THYMIC SYNDROMES 

 A. SYNDROMES OF THYMIC HYPERPLASIA. 



The thymus is affected by acute or chronic affections 

 (Roger and Ghika), but this reaction is purely histological. 

 There are no clinical evidences of this 



1 Clinically the administration of thymus extract controls menorrhagia and 

 metrorrhagia when due to functional hyper ovarian stimulation. Tn fact in cases of 

 uterine bleeding of obscure origin thymus can be used as a therapeutic test. 



