THE CONTINUITY OF LIFE 



237 





Fig. 160. — Regeneration and gra r ting in the Earthworm. A, regeneration 

 of removed anterior segments by the posterior piece. B, regeneration of pos- 

 terior segments by the posterior part, so that the worm has a ' tail ' at either 

 end. C, regeneration of removed posterior end by the anterior piece. D, three 

 pieces grafted together to make a long worm; E. two pieces grafted to form a 

 worm with two ' tails ' ; F, short anterior and posterior pieces grafted together. 

 Regenerated portions are dotted. (From Morgan.) 





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Fig. 161. — Regeneration of a Flatworm, Planaria maculata. A, normal 

 worm; cut across at line indicated. B, B\ and C, C, regeneration of anterior 

 and posterior parts of A to form complete worms. D, piece cut from a worm; 

 D 1 , D 2 , D 3 , D 4 , successive stages in the regeneration of D. E, 'head' from 

 which rest of animal has been cut off. E 1 , E 2 , E 3 , successive stages in the re- 

 generation by E of a complete body. F, similar experiment to E, but a new 

 'head' in reversed position is regenerated instead of a body, F 1 . (From 

 Morgan.) 



