The Cultivation of Araeba by Substances in Solution. 



The apparent resemblance of enucleated amebas to amebas 

 deprived of food suggested that some of the phenor^ena ex- 

 hibited by the non-nucleated cell might be the result of 

 starvation, and have no direct connection with the absence 

 of the nucleus. Accordingly, an attempt was made to supply 

 the amebas with adequate food substance.3. Since it v/as not 

 possible to get the enucleated organisms to take in food 

 particles, an effort was made to provide a medium in which 

 amebas could be nourished by the absorption of substances 

 in solution. 



It has been pointed out that no artificial synthetic 

 medium has ever been provided which was adequate to nourish 

 an animal cell ( Surrows and Neymann, loi"^), althc the 

 blood and lymph apparently constitute a natural synthetic 

 medium for the cells of higher' organisms. Even cells cul- 

 tivated in vitro depend upon the autolysis of neighboring 

 cells for their nourishment, and the attempt to cultivate 

 protosoa in nutritive organic media has met with complete 

 failure (Biedermann, 191G, pf;78; Doflein, p ro8). In the 

 light of recent experiments in nutrition, however, it 

 seems possible that such negative results rna-Y tie due 



(52) 



