THE AXIAL GRADIENTS IN HYDROZOA. 



357 



agreed with the results obtained by Driesch, Morgan, and Stevens. 

 These experiments of Child's are the only ones considered by 

 Banus and the false impression is thereby conveyed that no one 

 but Child had ever experimented upon the matter. Banus has 

 criticized these experiments of Child's on the grounds that they 

 are not extensive and that the differences recorded are in some 

 cases so slight that they may be due to experimental error. It 



A 



B 



FIG. 2. Diagram to show method of cutting unequal pieces for the experiments 

 given in Table VI. 2A, apical pieces half as long as basal pieces; 2B, apical 

 pieces twice as long as basal pieces. 



is true that no very extensive series of experiments were carried 

 out because Child felt that the point had already been settled 

 by the work of Driesch and Morgan and that any further experi- 

 mentation was superfluous. Such observations as he made were 

 therefore incidental to other matters. It is also true, as Banus 

 says, that the differences obtained were not very large, but since 

 they always vary in the same direction, the results cannot be 

 due, as claimed by Banus, to experimental variation. In Table 



