INTERRELATION OF THE EXDOCRIN ORGANS 925 



literature as regards the frequency with which thymus hypertrophy occurs 

 in thyroid disorders. He was able to collect 60 cases of Graves' disease 

 in which autopsy records were available. Of the cases in which the pa- 

 tients had died of an intercurrent affection, thymus hypertrophy was 

 noted in 44 per cent; of those dying directly of the disease, 82 per cent 

 showed hypertrophy; and of those succumbing to operation, 95 per cent 

 showed hypertrophy. Pappenheimer (1910), from a histological study 

 of the thymus glands of three patients having Graves' disease associated 

 with general status lymphaticus, reached the conclusion that the thymus 

 showed "renewal of growth" rather than mere persistence. Although 

 an enlarged thymus in Graves' disease is common, it is by no means always 

 found (Hilderbrand, 1918; Blackford, 1919). 



Thymus hypertrophy may be associated with simple congenital goiter. 

 In Switzerland, where the disease is endemic, the offspring of goitrous 

 mothers often show enlargement of both the thymus and the thyroid gland 

 (Birnbaum). Marine and Lenhart have also noted enlarged thymus in 

 young animals showing spontaneous thyroid hyperplasia. Whether the 

 simultaneous occurrence of hypertrophy in the two organs is simply a reac- 

 tion to a common cause, or whether hypertrophy of one conditions that of 

 the other, cannot from such observations be determined. 



That there is an element of true hypothyroidism in Graves' disease 

 is believed by Anders, Janney, and others. Congenital goiter rather 

 definitely signifies hypothyroidism. From the foregoing observations 

 one might conclude that the thymus possibly in a measure assumes the 

 thyroid function when the latter is deficient. That supposition receives 

 some report from the observations of Dustin and Zunz (1918). These 

 observers made a study of the weights of the thymus and thyroid glands 

 in normal men killed in the war. They found in general that if the 

 weight of the thyroid was small that of the thymus tended to be large, 

 and vice versa. 



The relation of the thyroid to the thymus has apparently received 

 relatively little attention at the hands of experimental investigators. R. 

 G. Hbskins observed that the offspring of female guinea-pigs to which 

 thyroid substance had been administered had larger thymus glands than 

 normal. Such an observation, however, is difficult to interpret. Gley 

 (1894) studied the condition of the thymus gland in cases of a few dogs 

 and rabbits from which the thyroid had been removed. Thymic atrophy 

 was noted. Similar results were obtained by Cadeac and Guinard in the 

 case of two lambs. Hofmeister, from a much more extensive series of 

 thyroidectomy experiments in young rabbits, obtained negative results. 

 Jeandelize, Lucien, and Parisot (1909), in 7 young rabbits from which the 

 thyroid had been removed, noted in every instance diminution of the 

 thymus weight. Worms and Pigache (1909) obtained somewhat similar 

 results. In their animals the thymus glands, a few days after thyroidec- 



