THE REGENERATION OF GONIONEMA. 5 



grew slowly and in two or three weeks some specimens had 

 developed only two to four tentacles, though several small bulbs 

 were present. In other specimens more tentacles formed, Fig. 5 



FIG. 5. 



showing seventeen bulbs and small tentacles on the regenerated 

 margin. 



II. EXPERIMENTS ON THE REGENERATION OF THE MANUBRIUM. 



In some cases the manubrium was removed by a circular cut 

 passing entirely through the jelly of the bell. The size of the 

 opening left varied in the different specimens but was not very large 

 in any individual. In other cases the upper half of the bell was 

 removed, thus leaving a very large opening. The rate of healing 

 did not seem to be at all dependent upon the size of the opening, 

 for, as noted below, some of those in which the upper half of the 

 bell was removed took less time to heal than some in which only 

 the manubrium was cut out. In all cases the cut edges gradually 

 contracted till they were touching. As soon as they met they 

 began to fuse and in a very short time the wound was entirely 

 healed. The rate of contraction and healing was not the same 

 in all the specimens. 



In the first set the contraction was slow, the cut did not com- 

 pletely heal until 60 hours after the operation. In the second 

 set the contraction was quite rapid. Twelve hours after the 

 operation the cut edges had met and twelve hours later had 

 entirely healed in half the specimens, though in the rest of the 

 specimens of this set 60-70 hours were required. In the third set 

 the cut edges had met and fused at the end of 48 hours. In the 



