548 C. M. Child. 



Series 74. Seven pieces were cut from the region lateral to 

 the pharynx (see dotted lines, Fig. 56). Figs. 63 and 64 show the 

 condition of these pieces eighteen days after section. All are 

 much contracted and are wholly incapable of movement. Some 

 new tissue has appeared on the cut surface but it is not visibly 

 differentiated; an irregular network of intestinal branches pro- 

 trudes a short distance into the new tissue. 



No further regeneration occurred and two weeks later all the 

 pieces were dead. 



C. GENERAL CONSIDERATIONS. 



According to the conclusions reached in the preceding paper 

 (Child, '04b) posterior regeneration from levels posterior to the 

 ganglia is affected only quantitatively by the removal of the gan- 

 glia, 1. e.y it is reduced in amount but is qualitatively complete; in 

 all cases the amount and rapidity of regeneration are directly 

 proportional to the size of the part removed. Anterior regenera- 

 tion on the other hand, is both qualitatively and quantitatively 

 incomplete in the absence of the ganglia and the amount of regen- 

 eration is inversely proportional to the size of the part removed. 

 When the ganglia are present, however, /. e., at levels anterior to 

 the ganglia the amount and rapidity of regeneration is directly 

 proportional to the size of the part removed. 



In the case of lateral regeneration the amount and rapidity of 

 regeneration are directly proportional to the size of the part re- 

 moved when the ganglia are present; when the ganglia are absent 

 amount and rapidity of lateral regeneration in the head region are 

 inversely proportional to the size of the part removed, while 

 farther posteriorly the proportion is direct unless the part removed 

 is very large, when it becomes inverse in consequence of the small 

 size of the piece and the unfavorable conditions for continued 

 existence. 



Posterior regeneration and lateral regeneration posterior to the 

 head region are affected only quantitatively by the presence or 

 absence of the ganglia, but the influence of the ganglia on anterior 

 or lateral regeneration in the head-region is qualitative as well as 

 quantitative. 



