THE DUCTLESS GLANDS. INTERNAL SECRETIONS. 197 



sumption of oxygen and therefore a more rapid breaking down of the tissues (for 

 which reason it is a familiar therapeutic procedure for reducing weight) . According 

 to Schondorff the body-fat is first transformed, the albumin not being attacked until 

 the fat has been reduced to a certain minimum. The substance (solely?) active 

 in this connection is iodothyrin, a body prepared in 1896 by Baumann, and con- 

 taining nitrogen, phqsphorus, and iodin. In some localities marked enlargement 

 of the thyroid gland (goiter) is quite common, and is not infrequently associated 

 with idiocy and cretinism. In those cases in which the goiter is designated a 

 follicular hyperplasia of the thyroid gland, the condition can be made to disappear 

 by the administration of preparations of the thyroid gland. Fr. Hofmeister found, 

 after extirpation of the thyroid gland in rabbits, degeneration in the cartilages and 

 disturbances in the growth of the bones. 



According to Gegenbaur the thyroid gland is an actively functionating organ 

 in some of the remote orders of animals (for example, among the tunicates, in 

 which it appears as a groove and secretes a digestive juice) , which in vertebrates 

 has undergone involution. 



The suprarenal bodies consist of a medullary and a cortical layer, and contain 

 compartments formed by connective tissue and bounded by blood-vessels. In 

 the cortical layer the compartments are oblong and radiate, while in the medullary 

 layer they are rather circular. The former contain (embedded in a reticulum) 

 polyhedral, nucleated, protoplasmic cells without walls, the substance of which 

 contains pigment and fat-granules, and is darker and more resistent than that 

 of the medullary cells. The medullary layer contains also small and multipolar, 

 large sympathetic nerve-cells. Both cortex and medulla are richly supplied with 

 nerve-fibers. The blood-vessels are relatively abundant. 



The suprarenal bodies contain the constituents of connective and of nervous 

 tissue, besides leucin, hypoxanthin, benzoic and taurocholic acids, taurin, inosite, 

 fat and pigment-forming bodies. Of inorganic substances potassium and phos- 

 phoric acid preponderate. 



The function of the suprarenal bodies is practically unknown. After extirpa- 

 tion of one suprarenal body, the other undergoes hypertrophy to double its original 

 size. Bilateral extirpation is followed by death, with the symptoms 'of poisoning 

 and paralysis. These symptoms, however, do not develop if a small piece is 

 allowed to remain. It appears, therefore, that the suprarenal bodies also are 

 designed to destroy a poisonous substance in the body, which exhibits its injurious 

 effects after extirpation of the glands. The injection of a watery extract of supra- 

 renal body is said to arrest temporarily the toxic symptoms that make their 

 appearance after extirpation. 



Injection of the extract obtained from the medullary substance of healthy 

 animals (and which does not contain albumin and is soluble in alcohol) gives rise 

 to marked contraction of the arteries and increase in blood-pressure, slowing of 

 the pulse by central stimulation of the vagus, or even arrest of the auricles. After 

 section of the vagi the heart again becomes more rapid and stronger, owing to the 

 action of the drug on the substance of the heart itself. The extract has the same 

 constricting effect on small blood-vessels and hence raises the blood-pressure. The 

 splanchnic nerve contains vasodilator and secretory fibers for the organ. The 

 breathing is superficial and accelerated. Large doses injected intravenously cause 

 death through enfeeblement of the central nervous system, dyspnea, and cardiac 

 paralysis. In frogs muscular paralysis results. 



Brown-Se"quard believed that one of the functions of the suprarenal bodies 

 is to inhibit excessive pigment-formation. In agreement with this view, Tizzoni 

 found, after extirpation of the organs (in rabbits), abnormal pigmentations, espe- 

 cially on the lips, and Boinet in the blood and subcutaneous cellular tissues (of 

 rats) . In conditions in which erythrocytes are dissolved and converted into pig- 

 ment the suprarenal bodies are found to be especially rich in pigment. In the 

 medullary layer a substance is formed that becomes brown when exposed to the 

 air or brought in contact with alkaline tissues. In man the skin often presents a 

 bronzed pigmentation (bronzed skin, Addison's disease) when the suprarenal 

 bodies and their capsules have undergone (tuberculous) degeneration. _ In hemi- 

 cephalous monsters the organs are atrophic, even when only the anterior halves 

 of the hemispheres are absent. 



Hypophysis Cerebri. CoccygeaL Gland. Carotid Gland. But little is known 

 concerning the function of the pituitary body. The posterior portion belongs to 

 the infundibulum, and here the nervous elements are, to a large extent, displaced 

 by connective tissue and blood-vessels; while the anterior portion represents a 



