VASCULAR OR DUCTLESS GLANDS. 161 



or lymph and in some unknown way influences favorably tissue 

 metabolism. This view of the function of the thyroid is supported 

 by the fact that successful grafting of a portion of the thyroid be- 

 neath the skin or in the abdominal cavity will prevent the usual 

 symptoms which follow thyroidectomy. The same result is obtained 

 by the intravenous injection of thyroid juice or by the administra- 

 tion of the raw gland. It was shown by Murray that myxedematous 

 patients could be benefited, and even cured, by feeding them with 

 fresh thyroids or even with the dry extract. 



The chemic features of the material secreted and obtained from 

 the structures of the thyroid indicate that it is a complex proteid 

 containing iodin, which, under the influence of various reagents, 

 undergoes cleavage, giving rise to a non-proteid residue, which 

 carries with it the iodin and phosphorus. The amount of iodin in 

 the thyroid varies from 0.33 to i milligram for each gram of 

 tissue. To this compound the term thyroiodin has been given. The 

 administration of this compound produces effects similar to those 

 which follow the therapeutic administration of the fresh thyroid 

 itself : viz., a diminution of all myxedematous symptoms. In normal 

 states of the body, thyroiodin influences very actively the general 

 metabolism. It gives rise to a decomposition of fats and proteids 

 and to a decline in body-weight. In large doses it may produce 

 toxic symptoms : e. g. } increased cardiac action, vertigo, and glyco- 

 suria. 



The Hypophysis Cerebri. This is a small body lodged in the 

 sella turcica of the sphenoid bone. In consists of an anterior lobe, 

 somewhat red in color, and a posterior lobe, yellowish-gray in color. 

 The former is much the larger and partly embraces the latter. The 

 anterior lobe is developed from an invagination of the epiblast of 

 the mouth cavity, and consists of distinct gland tissue. The posterior 

 lobe is an outgrowth from the brain, and is connected with the 

 infundibulum by a short stalk. It has been suggested that the term 

 infundibular body be reserved for the posterior lobe. This dis- 

 tinction appears to be desirable, inasmuch as in their origin and 

 structure they are separate and distinct bodies. 



Removal of the hypophysis cerebri, or the pituitary body, is always 



followed by a fatal result, preceded by symptoms not unlike those 



which follow removal of the thyroid : viz., anorexia, tremors, spasms, 



etc. Degeneration of the hypophysis has been found in connection 



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