RECONSTITUTIONAL PATTERNS IN EXPERIMENT 



373 



by a number of longitudinal incisions close together and so placed that, 

 when contraction and distal-proximal union occur, distal and proximal 

 lacerations will come together, much more new tissue is formed in the 

 course of union, and in some cases a complete new disk with normal 

 number of tentacles and with mouth and esophagus develops from the 

 lacerated region, and development of more or less of the body follows 



B 



C D 



Fig. 126, A-D. — Development of tentacle groups and new axiate patterns in "rings" of 

 Harenactis attemiata; further explanation in text (from Child, 1909c, 1910c). 



(Fig. 126, D). The activation following laceration and union has deter- 

 mined a bud which becomes an entirely new polar axis and gives rise to 

 the distal parts of a normal individual. Here the old mesenteries are not 

 concerned, but the normal number of new mesenteries of a young indi- 

 vidual develops. It seems beyond question that the larger amount of new 

 tissue developing and probably a more intense and extensive activation 

 following the laceration are factors in determining the entirely new axis 

 of completely normal character as far proximally as it develops. Evi- 



