94 



CLAUDE W. MITCHELL 



Mass cultures of A and D 



The question now arose — were the stocks, thus isolated in A 

 and D, unable to produce the humped type, or had the conditions 

 in regard to some essential, but as yet unrecognized, factor been 

 unfavorable to its production? To determine this, thirteen indi- 

 viduals were isolated from the pedigree cultures and allowed to 

 reproduce in as many mass cultures. The results are given in 

 table 2. 



TABLE 1 



History of pedigree Series A 

 Gen. = generation; ind. = individual; sac. = saccate; fol. = following 



' One individual dead. 



