474 



C. M. CHILD. 



basal ends, but in Fig. n a basal end is developing opposite the 

 lateral hydranth and in Fig. 12 two hydranths have developed 

 from the lateral outgrowth. Fig. 13, a piece of another series 

 from 70-80 mm. animals three days after section is another case 

 of two lateral hydranths. 



10 



\J 

 ii 



A 



lM"f 



FIGS 9-13. Other cases of lateral hydranth development from region 

 of growth determined by injury. Figs. 9-12 from pieces including the 

 whole naked region of 50-60 mm. animals. Fig. 13 from piece including 

 whole naked region of 70-80 mm. animal. The figures are slightly above 

 natural size. 



This lateral operation has been performed on thirty-five stem 

 pieces and of these fifteen, or forty-three per cent, have given 

 rise under standard conditions to new lateral axes consisting of at 

 least a hydranth and more or less stem. Twenty pieces, fifty- 

 seven per cent., healed without giving rise to new axes. Among 

 the new lateral axes three, i.e., nine per cent, of the total, became 

 complete by the development of a basal end from the lateral stem 

 region opposite the lateral hydranth. 



It has been shown in earlier papers (Child, '26^, '270, fr), that 

 either cut end or both, or any other region of a piece may develop 

 as a basal end under inhibiting external conditions. In the light 

 of these results it is to be expected that regions of lateral injury 

 may also be made to develop as basal structures under inhibiting 



