344 



Florence Peebles 



of the minor component (D). Eleven developed oral hydranths 

 on the long piece and nothing on the shorter one. Two developed 

 hydranths on the short piece only, and two on the aboral end of 

 the long piece only. In one case new hydranths appeared simul- 

 taneously on the two exposed ends. In all grafts where a long 

 and a short piece are united, the formation of a new hydranth is 

 always slower in the short piece. In six of the eleven grafts that 

 developed the hydranth first at the oral end of the major compo- 

 nent, the hydranth that formed later on the other end came partly 

 from the long piece and partly from the short one, i. e., the distal 

 tentacles developed in the minor component, and the proximal in 

 the major component. In these the development was always 

 slower. 



4 GRAFTING A SHORT BASAL PIECE ON THE DISTAL END OF THE 



SAME STEM 



In order to test the influence of a long distal piece on a short 

 basal one, a second series of experiments was made. This time 

 the hydranth was cut from a piece of stem measuring 3 to 4 cm. 

 From the basal end of this piece a short piece (2 to 3 mm.) was 

 cut off, and grafted in the opposite direction, on the oral end of 

 the same stem (Fig. 18). The results from these experiments 

 were not surprising. Here no influence seemed to be exerted by 

 the major component, as the following table shows. 



No very definite conclusions can be drawn from this table, or 

 from any of the other series in this experiment. The major com- 

 ponent apparently took no part in the formation of the hydranth 

 in the smaller piece. From constant observation of the behavior 

 of grafts composed of a short and a long piece, I am inclined to 

 believe that the size of the short piece has more to do with the rate 



