198 



K. S. LASHLEY 



TABLE 22 



Averages of the first six and of all later buds produced by polyps selected for a lart 

 and of those selected for a small number of tentacles 



as usual but those of the minus selected group increased more 

 rapidly and to a greater extent than that of the plus selected one. 

 This is shown in figure 9. The averages of the first six and of 

 all later buds of the two groups is given in table 22, The differ- 

 ence in favor of the plus selected group in the first six buds is 



70 



6,5 



60 



Fig. 9 The average number of tentacles of the successive buds produced by 

 the last selected generation in the selection experiment; ( ) ancestry selected 



for a large number of tentacles; ( ) ancestry selected for a small number 



of tentacles. 



0.217 ±0.044. There is no significant difference between the 

 later buds of the two groups. 



Since not all parents produced the same number of buds it 

 seemed possible that this decrease in the difference between the 

 groups might be due to a larger percentage of the progeny of more 

 vigorous polyps among the buds produced after the sixth, but 



