62 ANATOMY 



rine's 433 suggestion that the involution represents a physiologi- 

 cal response due to diminished demands for cortical tissue 

 because of the antagonistic action of the thyroid takes no ac- 

 count of the morphological features of the process nor of the 

 results in the mouse where the degeneration occurs sometime 

 after birth. In pneumonia also, as we have already seen, an 

 actual stimulation of the growth of the true cortex occurs while 

 degeneration of the androgenic zone proceeds at an undi- 

 minished rate. 



The peculiar deposition of lipids characteristic of the involu- 

 tion of the androgenic zone is evident in early fetal life (4th 

 month) in the cells of the innermost cortical layer which sur- 

 round the medullary vein. 694 This lipid, as judged from its 

 staining reactions and appearance under the polarizing micro- 

 scope, differs from that which later characterizes the cortex 

 proper. In those animals in which no involution occurs, the 

 appearance of the lipoidal deposits in the cortex at birth re- 

 sembles that of the adult gland. 



It is interesting to note that in hemicephaly, the adrenals 

 at birth, as Morgagni first observed in 1723, are extremely 

 small. 696 This is due to the absence of an androgenic zone 

 associated with maldevelopment of the reproductive system. 182 

 In spina bifida or hydrocephalus no abnormalities of the an- 

 drogenic zone are observed. The period of infancy during 

 which the androgenic zone is at its height of activity is also a 

 period of activity of the interstitial cells of the testes which is 

 in accord with the view that the androgenic tissue exerts a 

 masculinizing effect analogous to that exerted by these cells. 



In the adult human adrenal one can observe a thin juxta-med- 

 ullary zone which differs from the rest of the cortex by the 

 disposition of the cells and their chemical and morphological 

 properties. 231 These cells are osmophilic and pigmented and 

 are denoted by some writers as part of the reticularis. Others 

 have described these cells as "embryonic in character." As 

 pointed out by Goormaghtigh 231 these cells which border the 



