REGENERATION IN PLANARIAN PHAGOCATA GRACILIS. 165 



3. Pieces containing only some of the lateral pharynges 

 develop a new median pharynx at the anterior end of the pharyn- 

 geal chamber and new lateral pharynges both in front of and 

 behind the old lateral pharynges. 



4. Pieces cut behind the old pharyngeal chamber develop a 

 new median anterior pharynx and new lateral ones are added 

 from before backwards. 



5. Old lateral pharynges do not appear ever to be substituted 

 for the old median pharynx if this is removed. 



