284 INTERNAL SECRETION 



seen in fatty degeneration and cloudy swelling is protagon, and 

 this is in accordance with the theory of Kaiserling and Orgler. 



O. Herrmann (1905) minutely investigated the double refrac- 

 tive substances resembling myelin present in the suprarenal 

 cortex. The double refractive substances are present in varying 

 quantities as physiological constituents of the human suprarenal 

 from the embryonal state until old age. They are present in the 

 form of round globules of varying size, and they are characterized 

 by the following reactions : they resist alkalies and acetic acid ; 

 they stain slightly yellow with Lugol's solution ; when warmed, 

 pink with Millon's reagent; they are readily soluble in chloroform 

 and ether ; in alcohol they dissolve slowly ; they stain brown with 

 osmium, at the same time losing their double ref ractivity ; when 

 fixed in Flemming's solution they stain black. 



The most important thing about these double refractive sub- 

 stances, however, is their attitude towards neutral red ; they do not 

 stain with this reagent. On the other hand, in addition to the 

 globules, myelin masses are found, and these stain with neutral 

 red. In badly fixed sections where the nuclei do not stain, the 

 neutral red staining of myelin bodies is more easily recognized. 

 It is evident then that the double refractive granules are not 

 identical with the myelin substances, which colour with neutral 

 red (Albrecht). 



After hardening in formalin, needle-shaped crystals stained 

 with fat-ponceaux are observed in addition to the globules; 

 these crystals take up dyes, and are in many instances still refrac- 

 tive. Double refractive globules similar to those in man are found 

 in large numbers in rats, but they are not present in guinea-pigs, 

 nor, as a general rule, in rabbits. The cells of the suprarenal in 

 rabbits are filled with small, polyhedral granules, which frequently 

 combine to form largish scales, are not double refractive, and in 

 fresh preparations do not stain with neutral red. 



These granules stain with neutral red in preparations in which 

 autolytic processes have occurred, either when kept in an 

 incubator, or in the abdominal cavity, free or enclosed in india- 

 rubber bags. Their double refractivity is not, however, increased, 

 and there was no actual proof of the transformation of the poly- 

 gonal granules into larger myelin forms or into globules. Colour 

 reactions show that fatty acids are present in the external layer 

 of disconnected suprarenal grafts. This is most readily explained 

 by the assumption that the leucocytes in combination with the 

 fluids of the body which penetrate into the external layer, bring 

 about a process of resorption, which is attended with a splitting 

 up of myelin. 



Herrmann was unable to obtain from the results of his 

 experiments any further information concerning the nature of the 

 amorphous masses in the suprarenal of rabbits, as well as of the 

 double-refractive globules which occur in profusion in the supra- 

 renal of man, and in small quantities in the suprarenal of rabbits. 



