INHERITANCE IN ASEXUAL REPRODUCTION 



181 



Fig. 4 Diagram of the size relations of Clones A and D. From camera draw- 

 ings of polyps of mean size. 



over more than half the period of cultivation so that environ- 

 mental differences should have averaged out. The polyps 

 measured were selected because of their relationships, so that 

 the personal factor, an unconscious selection of extremes, can 

 have played no part in producing the difference. 



All the differences recorded are between groups which had 

 been kept under environmental conditions as nearly uniform as 

 possible. The polyps in individual cultures were fed in irregular 

 order in order to insure a uniform distribution of food. In the 

 mass cultures the parallel series of the two clones were given 

 uniform treatment and an interchange of water in the parallel 

 cultures was made frequently. The evidence seems to prove 

 conclusively that some internal, hereditary factor caused the 

 differences between the clones. 



This conclusion is still further verified by an analysis of the 

 data from the individual cultures. In order to test the constancy 

 of the difference, the time during which the clones were culti- 

 vated was divided arbitrarily into intervals of five days and 

 the mean number of tentacles of all buds produced by each clone 

 during each five-day period was computed. Table 14 and figure 



