446 MANUAL OF HISTOLOGY. 



As regards the composition of the suprarenal body, we only possess a 

 few notes at present. Its specific gravity is, according to Krause and 

 Fischer, 1*054. It contains leucin and myeliri in large quantities 

 (Virchow). Holm has also met with inosite and taurin in the ox. 

 Among the graminivora, hippuric and taurocholic acids are also stated by 

 Gloez and Vulpian to be present in the organ in question (?) Another 

 matter was also discovered in the medulla by Vulpian, and its presence 

 confirmed by Virclww, which became red on exposure to the air and on 

 the addition of iodine in solution, and blackish blue under the action of 

 chloride of iron. 



We are still entirely in the dark as to the physiological significance of 

 the suprarenal bodies. They are, however, liable to undergo many 

 morbid changes, which have recently become the subject* of much con- 

 sideration in their relation to the so-called Morbus Addisonii. This 

 manifests itself in very emaciated subjects as a very deep discoloration 

 of the skin, together with disorganisation of the suprarenal bodies. The 

 tingeing of the skin is produced by the presence in the deeper layers 

 of cells of the rete mucosum of either a diffuse or very finely molecular 

 pigment of a yellowish or yellowish brown colour. That peculiar colouring 

 matter in the boundary zone between the medullary and cortical portion of 

 the organ which we have already considered above, is very possibly con- 

 nected with this very obscure and enigmatical phenomenon. 



The suprarenal body is developed at the same time as the kidney, but 

 independent of it, from an aggregation of cells in the middle germinal 

 plate. It is a curious fact, that during the earlier portion of intra-uterine 

 existence these bodies at first exceed in magnitude the urine-secreting 

 organs. At about the twelfth week in the human subject they are about 

 equal the latter in size, and from that on they remain more or less 

 stationary. The histogenesis of these organs, however, is not yet quite 

 settled. 



238. 



The pituitary body, or hypophysis cerebri, was formerly supposed to be 

 a glandular structure, but was subsequently classed among the nervous 

 organs. 



Present in all five classes of vertebrata, but smallest in man arid the 

 mammalia, it consists in the latter of two portions or lobes. In the 

 smaller posterior part, which is greyish in colour, we meet in a connective- 

 tissue substratum with fine isolated nerve tubes, cells resembling ganglion 

 corpuscles, a quantity of sustentacular connective-tissue, with fusiform 

 cells and blood-vessels, but no glandular elements. 



The anterior lobe, much larger and redder, has by no means the same 

 structure. It is traversed by a canal according to Peremeschko, and, as 

 was found many years ago by Ecker, it possesses great similarity with the 

 so-called blood-vascular glands. Here we encounter, within a connective- 

 tissue framework very richly supplied with blood-vessels, roundish or oval 

 glandular cavities, measuring in man and among the mammalia 004:96- 

 0'0699 mm. These are occupied by cells of about 0'0140 mm. in 

 diameter, with tolerably large and finely granular bodies. Here also we 

 find, according to Ecker and Peremeschko, a colloid metamorphosis of the 

 cells, like that which takes place in the thyroid gland. The canal, whose 

 form is very various in different animals, is lined among the latter with 

 flattened cells, which in man are ciliated. It is continuous with the 



