274 INTERNAL SECRETION 



arranged in such a way that the smallest is nearest to the nucleus. 

 At the cell periphery they are surrounded by the layer containing 

 the lipoid granules. Where, however, as the result of the group- 

 ing of the cortical cells, the juxtaposing cell surfaces are free from 

 lipoid granules, in fuchsin preparations these areas are seen to be 

 crowded with fuchsinophile granules. There is no evidence to 

 show that these granules are changed into lipoid granules. The 

 effect of ether upon sections is to dissolve, not only all the lipoid 

 granules stained with osmium, but also a large proportion of 

 the fuchsinophile granules, the remaining portion of the latter 

 remaining unchanged (Plecnik). 



The cells of the suprarenal cortex also contain pigment. This 

 is seen in the inner layer, the zona reticularis, where it takes the 

 form of yellowish granules, even in sections coloured by the 

 ordinary nucleus and cytoplasm stains. These granules colour 

 black with Heidenhain's iron haematoxyjin, and a deep grass- 

 green with Unna's polychrome methylene blue and differentiation 

 with glycerine ether. In these preparations, even small quanti- 

 ties of pigment are clearly visible against the blue nuclei and the 

 unstained cytoplasm. The sections should not have been pre- 

 viously fixed in osmium solutions. When fixed in Altmann's 

 mixture the pigment loses its yellow colour, becomes a dirty green, 

 and is readily distinguished from the intensely black lipoid 

 granules. The embryonal suprarenal contains no pigment ; 

 Plecnik found that it was present in very small quantities in the 

 suprarenal of an infant 6 days old. 



The pigment is found both in free cells and in those which 

 contain cortical granules. If sections which have been stained 

 with osmium are treated with ether and then coloured with iron 

 hasmatoxylin, large clear spaces will be observed in the zona 

 reticularis in place of the black lipoid granules; while the pigment 

 granules, also coloured an intense black, will still be visible in the 

 alveolated body of the cell. According to Dostojewsky, this 

 alveolate network represents, not the filamentous portion only, 

 but the entire cell-plasm. Thus it appears that the lipoid granules 

 occupy the plasmic spaces, while the pigment granules are situated 

 in the cytoplasm itself (Plecnik). 



CHEMISTRY OF THE SUPRARENAL, EXCLUSIVE OF 



ADRENALIN. 



In spite of the immense interest which has been aroused in 

 the physiologically active substance of the suprarenals, or perhaps 

 because attention in general, including that of chemists, has been 

 focused upon the physiological side, the advanced methods of 

 modern chemistry have, up to now, supplied only the first begin- 

 nings of a knowledge of the chemical constitution of the supra- 

 renal. 



