RELATIONS OF THE ORGANS TO ONE ANOTHER. 605 



the main thyroid gland varies in different animals. Their significance has 

 only very recently been realized. 



If the thyroid gland is completely removed from the body, or its functions 

 fail for any reason, peculiar changes result. They were first observed 

 and described by William Gull l in 1874. The most prominent symptom 

 is a thickening of the skin. It appears, on account of the increased 

 amount of mucin in the subcutaneous connective tissue, as an edematous 

 swelling. For this reason Ord 2 gave to the disease the name, myxedema. 

 Subsequently the swelling goes down, and the skin then appears more 

 atrophied. The secretion of the glands in the skin ceases, and the latter 

 becomes hard and dry. Metabolism is disturbed, and so is the temperature 

 of the body, and the mechanism for regulating the body-temperature. 

 The most striking disturbances are those of the muscular and nervous 

 systems. They are of various kinds. Sometimes there is evidence of 

 increased sensitiveness, while in other cases the change is entirely in the 

 other direction. The various effects, which also change as the disease 

 progresses, may be due to the more or less complete failure of the functions 

 of the gland. 



J. L. Reverdin, A. Reverdin, 3 and afterwards Theodor Kocher, 4 had 

 considerable opportunity to study the effects of the total extirpation of 

 the organ in man. They found on the whole the same symptoms as in 

 myxedema. Kocher embraced the whole complex of symptoms under 

 the name of Cachexia strumipriva. It is not a simple disease. In general 

 the same characteristics are manifest. In individuals which have not 

 attained full growth, extirpation of the organ causes a tardy develop- 

 ment of the length of the bones. We find here reminiscences of cretinism. 

 It is specially noteworthy that individuals quickly lose the ability to 

 reason. Finally idiocy may result. 



After J. L. Reverdin had published his first results, physiologists recalled 

 the experiments of Moritz Schiff 5 made in 1859, with regard to the total 

 extirpation of the thyroid gland in animals. Schiff showed that dogs 

 did not long survive the operation. They died within from 4 to 27 

 days. There is to-day no doubt prevailing as to the correctness of 

 his observations, although the cause of the different behavior of vari- 

 ous classes of animals has been much disputed. With dogs and cats 

 death results quickly and usually in a convulsive attack (tetany). Muscu- 



1 Trans. Clin. Soc. London, 1874. 



2 On Myxoedema. Medic-chirurgical Transactions, Second Series, 43, 57 (1878). 



3 J. L. Reverdin: Revue medicale de la Suisse romande, 2ieme anne"e, 539 (1882), 

 and 3ieme ann6e, p. 47 (1883). J. L. Reverdin and Aug. Reverdin: ibid. 3ieme ann6e, 

 No. 4, pp. 169, 233, 309, and 686 (1883). 



4 Arch. Clin. Chir. 29, 254 (1883). 



6 Arch, exper. Path. Pharm. 18, 25 (1884). 



