2I 4 



SENESCENCE AND REJUVENESCENCE 





90 



91 



93 



FIGS. 86-93. Reconstitution in short pieces of Planar ia dorotocephala: Fig. 86, 

 body-outline, indicating levels of section; Figs. 87-89, biaxial and single heads formed 

 independently of other parts; 90, biaxial form with partial body; Fig. 91, headless 

 piece without reconstitutional changes in the anterior region; Fig. 92, anophthalmic 

 form in which anterior region has undergone reconstitution into the anterior and 

 middle body-region of a whole worm; Fig. 93, biaxial tails. - 



