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Florence Peebles 



long pieces are grafted together in the same direction, they may 

 act as one piece, a hydranth forming first at X and later at T 

 (Fig. 2) but a large per cent form hydranths simultaneously at 

 the oral ends of each component (Fig. 4). The question naturally 

 arises as to the result if two pieces are grafted together by their 

 aboral ends so that the two oral ends are exposed. 



Expemnent I. Two pieces each measuring about 3 cm. 

 with the hydranths still attached, were grafted together by their 

 aboral ends (Fig. 13). At the end of twenty-four hours the hy- 

 dranths were removed, together with i cm. of the stem. The 

 graft {A) consisted of two components of equal lengths whose 

 aboral ends had been united for twenty-four hours and whose oral 

 ends were exposed at the same moment by a fresh cut. This 

 experiment was repeated, with modifications, several hundred 

 times. The results can not be combined in tables without much 

 repetition, therefore I shall merely give one representative series. 



In this series no hydranths formed at the graft line. In most 

 cases the two components acted as one piece forming a hy- 

 dranth at one end only, or first on one end, and then on the other. 

 Whether stolons would have developed later, I can not say, for the 

 pieces were kept only four or five days. At the end of that time 

 although two sets of hydranths developed on some pieces there was 

 no sign of stolon-formation or pushing apart at the aboral ends. 

 That one piece is influenced by the other seems evident from the 

 results. Only five grafts formed hydranths on each end at the 

 same time, while ten produced one first at one oral end, and then 

 after one to two days, at the other oral end. Ten more formed 

 hydranths at one of the oral ends and nothing at the other. 



Experiment 2. In a second experiment one component was cut 

 close to the fine of graft (Fig. 14, 2). In this way, it was thought. 



