Thr Bi'hav/or of Loxophylluin 



413 



be followed in its course witliour any difficulty. 1 he short oral 

 margin of the posterior cut piece was simply stretched out to form 

 the whole oral and anterior margins of the regenerated individual. 

 Essentially the same method is followed in the regeneration of 

 comparatively small transverse pieces (see Fig. 3). 



The experiment was then tried of reducing the oral margin still 

 more. By making a cut across the anterior end and a longitudinal 

 cut near the oral side the whole oral margin was removed except 

 a small part near the posterior end of the body (see Fig. 3). In 

 this case the amount of cut surface exposed was very much greater 

 than in the previous experiments, so much so that it seemed mcred- 



Fig. 4 Regeneration of a specimen from which the anterior end and most of the ciliated oral 

 margin was cut off. 



ible that the small remaining part of the ciliated margin could be 

 extended so as to stretch over it, especially since the part remain- 

 ing is one that gets little stretching during the usual activities of 

 the animal. As might be expected, although it was stretched 

 around the oral side to a certain extent, this part failed to give 

 rise to any but a small part of the new oral side. The new oral 

 margin with its differentiated structures had therefore to be pro- 

 duced by a new method. The piece began to elongate and become 

 narrowed and rounded in front. Owing to the lack of the con- 

 tractile and extensile elements of the oral margin the character- 



