SUPRARENAL BODIES 



205 



SUPRARENAL BODIES (ADRENALS;. 



The suprarenal bodies consist of two parts of totally different origin. The 

 cortex is derived from the mesothelium covering the inner aspect of the fore-part of 

 the Wolffian body, immediately lateral to the attachment of the mesentery and 

 in front of the germinal epithelium (fig. 256). It appears as a series of buds which 

 fuse into a cellular mass imbedded in the mesenchyme of the Wolffian ridge. 

 The cells become arranged in columns, and the three zones characteristic of the 

 cortex of the adult gland are early to be made out; The whole body consists 



sy sy' 



*4; 









cap. * 





if 



^Jm 



;;;,, 





m 



?&$vr 



&&: '. t '!> 



-* * *v ^f3X 



XNJ^& 



> VjV/-\ 





FIG. 258. TRANSVERSE SECTION OF^THE SUPRARENAL BODY OF A HUMAN EMBRYO OF 15'5 MM. 



(T. H. Bryce.) 



sy, sy, the abdominal sympathetic ; sy', sy', groups of cells extending from the sympathetic into the 

 suprarenal ; cap, capsule of the gland ; a, aorta. 



at first of cortical tissue (fig. 258), and in the centre the trabeculae are arranged 

 in an irregular network with vessels (sinusoid in nature) in the meshes, and 

 opening into a central venule. The appearance is very like that of a liver 

 lobule. The medulla is derived from the sympathetic, and is produced by an 

 ingrowth of cell-groups on the mesial aspect of the gland. In an embryo 

 at the end of the second month the abdominal sympathetic consists of 

 numerous groups of cells in the neighbourhood of the aorta. As we have seen 

 {p. 133), these groups of cells are derived from the ectoderm, and have wandered 



