550 



Messrs. Cramer and Krause. Carbohydrate [June 10, 



Plate 15. 



Fig. 5. — Adult specimen of A. tuberosa, with the tentacles and hillocks wholly retracted 

 and the potassium salt or salts diffused in the underlying cytoplasm more 

 than was the case in the form indicated in Fig. 4. Cobalt sodium hexanitrite, 

 glycerine-ammonium sulphide, x 750. 



Fig. 6. — The terminal portions, greatly magnified, of two of the tentacles of the specimen 

 from which fig. 3 was drawn. Cobalt sodium hexanitrite, glycerine-ammonium 

 sulphide, x 3200. 



Fig. 7.— The terminal portions of two tentacles of a specimen of A. tuberosa, stained to 

 show the distribution of fat in them. Formol, scarlet red, glycerine, x 1680. 



Fig. 8.- — Specimen of A. tuberosa unstained, to show the distribution in it of the pigment 

 which it absorbs from the vegetable forms on which it preys. The hillocks 

 and tentacles are free from it. Formol, glycerine, x 500. 



Fig. 9. — Specimen of A . tuberosa seen with its anterior border tilted forward, showing the 

 distribution of potassium salts in the grooves formed by the two parallel folds 

 of the lorica. Cobalt sodium hexanitrite, glycerine-ammonium sulphide, 

 x 450. 



Carbohydrate Metabolism in its Relation to the Thyroid Gland. — 

 The Effect of Thyroid Feeding on the Glycogen-content of the 

 Liver and on the Nitrogen Distribution in the Urine. 

 By W. Cramer and E. A. Krause. 



(Communicated by Sir E. A. Schiifer, F.R.S. Received June 10, — Read June 26, 



1913.) 



(From the Chemical Laboratory of the Physiology Department, Edinburgh University. 



Introduction. 



Our present knowledge of the relation of the thyroid gland to metabolism 

 is based almost entirely on observations of the disturbances of metabolism 

 produced by the diseases of the thyroid gland. By the application of 

 physiological methods to patients suffering from Graves' disease or from 

 myxcedema an increase in the total metabolism and in the nitrogen meta- 

 bolism in Graves' disease on the one hand, a decrease in the total metabolism 

 in myxcedema on the other, have been definitely established. From these 

 facts the conclusion has been drawn that the secretion of the thyroid gland 

 increases the oxidative processes, so that an inadequate functioning of the 

 gland brings about the condition of obesity and depressed nitrogen metabolism, 

 characteristic of myxcedema. As regards the carbohydrate metabolism it 

 has been observed clinically that in Graves' disease there is sometimes a 

 tendency to alimentary glycosuria ; the opposite condition — an increased 



