560 VERA DANCHAKOFF 



nuclear chromatin the name of somatochromatin ; the chromatin 

 of the nucleus became known as idiochromatin. According to 

 Hertwig, the somatochromatin is activated iodiochromatin, the 

 potency to activity being in idiochromatin in a latent stage. 

 Subjected to certain conditions, idiochromatin may be trans- 

 formed into somatochromatin. The somatochromatin has a 

 trophic influence upon the cell activity, and is continually trans- 

 ferred from the nucleus to the cytoplasm. Since the extra- 

 nuclear chromatin is subjected in the cytoplasm to a gradual 

 destruction, the permanent emission of chromatin by the nucleus 

 would prevent the hypertrophy of the nucleus. 



Rtickert also considers the somatochromatin or tropho- 

 chromatin, as a permanent element in the cytoplasm, but draws 

 a strong distinction between the somato- and reproductive chro- 

 matin. The somatochromatin has trophic regulative function, 

 the reproductive chromatin is connected with transmission of 

 hereditary qualities. 



Schaudinn and Goldschmidt extend the distinction between 

 the two kinds of chromatin still farther. According to them, 

 the nuclei of every animal cell are duplex in their organization 

 and contain chromatin of reproductive and of merely somatic 

 function. The chromidial apparatus of the cell, by which name 

 the extranuclear chromatin is termed, arises from the somatic 

 nuclear substance. 



A somewhat different opinion is expressed by Schaxel. This 

 author comes to a conlcusion, that the extranuclear chromatin, 

 present in large masses in the egg and in the blastomeres of sea- 

 urchins is emitted by the nucleus at definite stages of cleavage. 

 Schaxel does not admit continuous emission of chromatin by 

 the nucleus. The chromatin particles in the cytoplasm, accord- 

 ing to him, are 'Kinetochromidien' and contain Weismann's deter- 

 mining biophores. During cleavage they undergo progressive 

 exhaustion and are not capable of synthesis in the cytoplasm. 



Thus the role of chromatin in the cytoplasm has been differ- 

 ently interpreted. It was considered by some investigators as 

 a substance, from which the nucleus endeavors to free itself, and 

 which finally disintegrates in the cytoplasm. Again others 



