ORGANIZATION AND GROWTH 



roots. Light has no deinon- 

 orientation of Antennularia. 



one side only, the animals 

 and the same occurs also in 

 uli, however, affect the orien- 



. 



strable effect upon the 

 Even when lighted from 

 continue to grow upward ; 

 the dark. 1 Contact stim- 

 tation. When the roots 



w 



FIG. 40 



\ 



X 

 X 



are brought in contact with a solid body, they attach them- 

 selves to it and grow over its surface. The stems and branches 

 do not possess this 

 form of irritability. 



3. With these pre- 

 liminary remarks, I 

 shall show how regen- 

 eration and heteromor- 

 phosis depend upon 

 the orientation of the 



1 \fl/ / 



\ 



\ 



\ 



W 



> i w 



FIG. 41 FIG. 42 FIG. 43 



stem with reference to the hori/on. (th (Fig. 42) represents 

 a piece cut from the stem of an Antennularian ; a is the 



'The specimen grew only slightly in the dark. This may, however, have hap- 

 1 only by chance. 



