198 DYNAMICS OF LIVING MATTER 



ment, part of the substance of the egg is laid aside as the germ from 

 which the sexual glands develop. While the rest of the egg is 

 transformed into the various organs of the body, this part remains 

 what it is ; namely, embryonic matter. This embryonic matter 

 begins to grow at a certain stage in the development. Miescher* 

 has investigated this phenomenon somewhat in the case of the salmon. 

 The salmon leave the ocean and migrate into rivers to spawn. 

 When they begin to go into the rivers their testicles and ovaries 

 possess little weight, while their muscles are powerfully developed. 

 At this time the testicle is only T oVo to T1j"o f the weight of the 

 whole animal, while a few months later it is 5 per cent of the body 

 weight. In the female fish the relative weight of the sexual glands 

 is still more considerable. According to Miescher, the salmon do not 

 take up any food while they are in the fresh water. The source of 

 material from which the sexual glands are built up must therefore be 

 in the animal. Possibly through an increase in hydrolytic processes 

 this material gets into the blood and is retained by the sexual glands. 

 Miescher found that the muscles apparently furnished the material 

 from which the glands are built up. The male and female animals 

 behave somewhat differently in regard to the utilization of the 

 material furnished by the muscles. In the sexual gland of the males 

 the protein taken up from the blood is' partly hydrolyzed, and the prod- 

 ucts, according to Miescher, protamin, guanin, sarkin, collect in the 

 spermatozoa. In the ovaries this hydrolysis does not occur, and the 

 protein of the blood is utilized for the building up of the eggs whose 

 mass is considerably larger than that of the spermatozoa. The hydroly- 

 sis of the muscles is due, according to Miescher, to lack of oxygen, 

 caused in his opinion by the diminution in the rapidity of the circula- 

 tion of the blood through the muscles at the time of the growth of the 

 sexual glands. 



* Miescher, Histochemische und physiologische Arbeiten, Leipzig, 1897. 



