346 



Fl 



orence 



Peehh 



which the circulation of one piece was distinctly separate from 

 that of the other (Fig. 19, F) were isolated in lot B. Another lot 

 (C) consisted of those in which the circulation was irregular, and 

 the last {D) in which no circulation whatever could be detected. 

 The rate of development of the hydranths is shown in Table 16. 



The behavior of the grafts is practically the same whether the 

 circulation is continuous or not. In each case a hydranth devel- 

 oped first on one piece and then on the other or on one piece only. 



Experiment 2. Two short pieces grafted together by their oral 

 ends. Pieces of the same length as those in the preceding experi- 

 ment were grafted together by their oral ends, so that the aboral 

 ends were exposed. They were separated as before into lots A, 

 B, C and D. The results from one series are shown in Table 17- 



1 1 



TABLE 17 



2 ll 



Of these thirteen grafts four developed simultaneously on the 

 aboral ends. Three formed one first on one end, then on the 

 other, five formed one on one end and none on the other, and one 

 developed a hydranth on one end and a stolon on the other. A 

 control experiment was made in which single pieces, the same length 

 as the entire graft, were cut. Out of eleven pieces, eight formed 

 a hydranth on one end and nothing on the other; two developed 

 a hydranth first on one end, and then on the other, and one devel- 

 oped a stolon on one end, and a hydranth on the other. 



Experiment j. Two short pieces grafted together by their aboral 

 ends. These pieces were the same length, and taken from the 

 same region of the stem, but were grafted by their aboral ends 



