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made, and when the end of the tentacle stump had become 

 romided and closed (as in fig. 2), the excised tentacle was still 

 open at its proximal end, but the infolding had increased and 

 the opening had diminished. There had been no contraction of 

 circular muscles, and the wall was strongly wrinkled in a longitudi- 



Fig. 4 Excised tentacle cut into three fragments, six hours after cuts were 

 made. The three pieces are placed in their original orientation. X5. 



Fig. 5 Same fragments as in figure 4, twenty-three hours after the cuts were 

 made. X 5. 



Fig. 6 Excised tentacle; a, three days after cutting; b, c, the portions of the 

 same tentacle thirty minutes after being cut in two. X5. 



nal direction (fig. 5, a). The wrinkles remained even after the 

 tentacle end became temporarily or permanently closed, — in fact 

 as long as the tentacles were kept alive. The proximal end of the 

 middle piece (b) was also open during the twenty-three hours of 

 observation (figs. 4, 5) and its wall was wrinkled. The opening 



