144 



C. M. CHILD 



contained no more worms of the proper size — were prepared as 

 follows: the worms were cut in water at room remperature and 

 each piece as soon as cut was dropped into a liter Erlenmeyer 

 flask full of KCN to¥oo m. After all pieces were cut the solu- 

 tion in the flasks was replaced by fresh of the same concentration 

 and the flasks were corked. After twenty-four hours the pieces 

 were rinsed and placed in water where they remained until regu- 

 lation was complete. Table 7 gives the results in percentages, 

 la-If being the controls in water and Illa-IIIf the KCN lots. 

 In the control the axial factor appears as usual in a and b, but 

 c shows only a slightly lower head and eye frequency than h, 



instead of much lower as in series 432 and 419 in the preceding 

 section. This is because in the present series the c-pieces include 

 a part of the second zooids, while in series 432 and 419 they were 

 almost wholly within the flrst zooid. 



The d- and e-pieces are almost exactly alike and show a much 

 higher frequency of heads and eyes than the c-pieces. The simil- 

 arity of the d- and e-pieces probably indicates that each of them 

 belongs to a different zooid for if d were the anterior and e the 

 posterior region of the same zooid the axial gradient would appear. 



Probably then the region c, d, e as indicated on the right side of 

 figure 46 consists of two zooids which have resulted from the phy- 



