DYNAMICS OF MORPHOGENESIS 



421 



S. The one-sixth pieces 



Figure 2 shows the region of body included in each of the one- 

 sixth pieces. In table 5 to 8 only records of the pieces 1 , 2 and 3 

 which represent the body of the first zooid are included. 



Comparison of tables 5 to 8 with each other and with table 1 

 shows that the susceptibility of the one-sixth pieces immediately 

 after section (table 5) is greater, but after twelve hours (table 6) 

 is less than that of whole worms. 



TABLE 5 

 Susceptibility to KCN 0.001 m of one-sixth pieces immediately after section 



