THE ADRENAL BODIES 247 



formation, and that the process of elaboration is completed in 

 the medulla. This view has been tentatively proposed by 

 Schafer and Herring, and more definitely formulated by 

 Abelous, Soulie, and Toujan. These authors believe that the 

 active principle can be obtained in small quantities from the 

 cortex, where it is manufactured from tryptophane. It is then 

 passed into the medulla and stored there. These views have 

 not received support, and the experimental evidence in their 

 favour is not convincing. 



Elliott and Tuckett have made an attempt to solve the 

 problem of a possible functional relationship between cortex 

 and medulla. Among mammals the guinea-pig is conspicuous 

 by the huge development of its adrenal bodies, the growth 

 being chiefly of cortex. They point out also that the lower the 

 animal is in the scale of vertebrates the larger is its stock of 

 chromaphil tissue. Gestation accelerates the growth of the 

 gland. 



As signs of secretory activity Elliott and Tuckett recognize 

 four substances in the glands : 



(1) A fatty substance. 



(2) A doubly refracting substance. 



(3) Brown granules of the cortex. 



(4) The chromaphil substance of the medulla. 



The first two are nearly related ; the doubly refracting 

 substance increases with rest, when the fat becomes less 

 abundant. In phases of " exhaustion " the doubly refracting 

 substance vanishes and the fat spreads over all the cortex. 

 But neither are essential factors in a generalized type of cortical 

 activity, for neither appears in the sheep. The brown granules 

 occur characteristically and plentifully in the guinea-pig, and 

 over a restricted area in the ornithorhyncus. They accumulate 

 with rest, and disappear very early in exhaustion ; the 

 cytoplasm of the cells in which they have been stored then 

 develops fat. Exhaustion of the medulla is shown by a 

 progressive thinning of its yellow stain with potassium 

 bichromate. In states of extreme exhaustion this stain 

 finally vanishes. 



The only indication found by Elliott and Tuckett of any 

 functional relationship between cortex and medulla is the 

 observation that the changes described above, both in cortex 



