KREATIN AND XANTHIN 319 



With atropine : 



Kreatin . 



0.005 gramme . . . No mitosis. 



0.01 . . . Mitosis. 



0.02 . . . Well-advanced divisions. 



Employing xanthin the presence of atropine is necessary : 



Xanthin. 



0.002 gramme . . . Early mitosis. 



If the jelly contained saturated solution 1 of xanthin, 

 well-marked figures were seen. 



We had now succeeded in inducing the reproduction 

 of leucocytes and lymphocytes first by the aniline dye 

 azur, then by a substance contained in the extract 

 of suprarenal gland, and by our experiments we were 

 able to infer that this substance is contained in the 

 extracts of other dead tissues. It has just been shown 

 that this inference is correct, because cell-division can 

 be induced by the crystalline extractive kreatin, which 

 is a constituent of the remains of all dead tissues. So 

 far, of course, we had only induced divisions with these 

 substances in vitro; but, as already pointed out, the 

 cells are under very detrimental conditions while being 

 experimented with, and it is more than probable that, if 

 they will divide in response to these substances in vitro, 

 they will more readily respond to them in vivo. 



Healing is caused by the proliferation of leucocytes and 

 lymphocytes, and, judging from the in-vitro experimenta- 

 tion, this proliferation is evidently induced by kreatin and 



1 Xanthin is sparingly soluble. 



