THE THYROID AND PARATHYROIDS 301 



Astley Cooper gave some account of the structure of the 

 thyroid and extirpated the gland from two pups ten weeks old. 

 The animals recovered after suffering from stupidity and 

 malaise. The animals were killed very soon after the opera- 

 tion. 



Moritz Schiff, during the years 1856, 1857 and 1858, carried 

 out a series of thyroidectomies upon various animals. Some 

 rabbits, some rats, some fowls, and some dogs survived the 

 operation, but several dogs, a cat, and a rat died after some 

 days. 



The earlier results of Schiff were apparently read before the 

 Royal Academy of Science in Copenhagen and then buried in a 

 work on the formation of sugar in the liver. It is not surprising 

 that they remained unnoticed for many years. Cretinism 

 had long been recognized, and in 1874 Gull described the condi- 

 tion which Ord, in 1878, called " myxcedema." In 1882 the 

 Swiss surgeons noted the symptoms of " cachexia strumi- 

 priva," or " operative myxcedema," after operations for goitre 

 in the human subject. 



After an interval of a quarter of a century Schiff was led by 

 the observations of Kocher and Reverdin in Switzerland to 

 take up the problem again. In 1884 he recalled his earlier 

 experiments of 1856-1858, and published the results of a new 

 series of investigations. In the rat and the rabbit, thyroid- 

 ectomy was not followed by any serious result. In the 

 dog and cat, however, complete removal was fatal. He 

 gives an admirable account of the nervous symptoms after 

 removal of the thyroid in the dog, and states that these may be 

 avoided by a previous graft of the thyroid of one dog into the 

 abdominal cavity of another. Other symptoms noted by 

 Schiff were general malaise, arrest of growth, and in two cases 

 oedema. 



It must be noted that some of these symptoms, particularly 

 those of a nervous nature, are at the present time attributed 

 to loss of parathyroid tissue which must have occurred when 

 the thyroid was extirpated in dogs and cats. 



Wagner and others confirmed Schiff's observations, and it 

 has been stated that the first-named author found an increased 

 response in the nerves to galvanic currents after removal of the 

 thyroid (and parathyroids) in cats. 



Horsley was the first to operate on monkeys. He states 



