Proceedings of Learned Societies. 155 



from the violence of the muscular efforts. Presently the opening 

 in the base extended to the margin, and up the right side of the 

 column, exposing to view the internal structure — the septa and so- 

 called craspeda. At 4 - 20, twenty minutes after the rent had reached 

 the right margin of the base, it extended to the left, and so divided 

 the whole base into two nearly equal segments. It is a curious 

 fact that the tentacles corresponding to the two parts now contracted 

 separately ; hitherto the contractions were convulsive, and set in 

 suddenly at intervals and altogether, now there was a distinct pause 

 between the convulsion of the upper and lower division, the upper 

 always preceding the lower by a few seconds. At 5T0 the walls of 

 the stomach could be seen strained across the fissure, and they 

 presently gave way, the rent extending right through the column 

 to the oral disc. This appears to suggest that the seat of the central 

 nervous system of Actinia occupies the base, as Spix thought he had 

 demonstrated, although this demonstration has been rejected by 

 every authority who has followed him. On one margin of the disc 

 the rent involved the base of one of the outer row of tentacles, and 

 extended along it. He was much interested in watching its pro- 

 gress along ■ the tentacle, as it seemed doubtful whether it would 

 tear along its whole length, or detach one or other half from its 

 attachment to the body. The strain seemed great on the parts, and 

 at last the lower half tore off from its base, and, immediately closing 

 into a perfect tube, hung as a branch from its parent trunk. The 

 wound in this, too, seemed to close at once when the strain was 

 taken off'. Dr. Bennett mentioned this apparently trivial detail as 

 it appeared to explain the occasional occurrence of the double or 

 branched tentacle which has been observed in Anihea cereus. At 

 5 - 45, less than three hours from the commencement of the process, the 

 division was complete, the upper half falling to the bottom of the vessel. 

 At 6 - 5 the lower followed it, and the two new individuals lay together 

 almost motionless. Next morning one attached itself to the glass, 

 and showed its base nearly perfect ; the other lay much in the same 

 place as the evening before. Dr. Bennett was unable to continue 

 his observations on these two animals any further ; the water in the 

 vessel became turbid, and many of its inhabitants died, including 

 the two AnthecE. They were able to move about for some days, but 

 never with activity. They seemed, however, to have quite closed up 

 their wounds. He could not examine them anatomically, as they 

 were so softened before removed from the vessel that dissection was 

 impossible. The others of the same species which were put into 

 the vessel had also tried to divide, and apparently in the same way, 

 from base upwards. The observation proves that division was com- 

 pleted, and that the two halves lived as independent animals for a 

 few days. The whole time which the division took, from the first 

 observation of the opening in the base to the complete separation of 

 the halves, was barely three hours. The exciting cause of the pro- 

 cess seems to have been the condition of the water in the vessel, 

 just verging on decomposition. The most important part of the 

 observation is the mode of the division. 



The only case recorded of a similar kind is in Gosse's Tenby, 



