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The mouth opens towards the food, i. e., towards the direction from 

 which the stimulating solution reaches it: the tentacles, when they 

 receive a motor stimulus, apparently passed on to them from the mouth 

 region, move in all directions till some happen to come into contact with 

 the prey. If an object is not placed satisfactorily in the mouth, it may 

 be temporarily ejected to be reswallowed later. In such a case, or if a 

 tentacle has secured some morsel, several tentacles bend over the frag- 

 ment to prevent its escape. The number of tentacles affected seems to 

 vary with the size of the capture, and a small piece taken by some 

 outer tentacles will be passed on to tentacles further and further 

 in, until those nearest the mouth deposit it there for digestion. If any- 

 thing swallowed is not completely digested, the inedible remains are 

 discharged in a characteristic manner; the centre of the disk is elevated 

 and the object slides outwards, the tentacles either do not hold it, or 

 separate and allow it to pass between them, and, especially in Anthea 

 cereus^ shrivel to very small dimensions. The facts here noted seem to 

 indicate that the tentacles are in part controlled (receive motor or inhibi- 

 tory stimuli) from the mouth region and perhaps we may say that the 

 nematocysts act as if controlled from the mouth region, at any rate in 

 Actinia and Anthea. 



Summarising the results discussed thus far, we may say, 



1) That the tentacles react to many contact stimuli. They show some 

 amount of differential reaction in this respect but, none the less, 

 carry all manner of unsuitable stuff to the mouth. 



2) That the tentacles are almost completely indifferent to the chemical 

 stimuli they are likely to receive under normal circumstances. 



3) That motor stimuli can be communicated from the lips to the ten- 

 tacles when the former have been stimulated, (especially chemically 

 stimulated). 



4) That motor stimuli can be communicated from the tentacles to the 

 mouth causing the latter to open when the former have been stimu- 

 lated (especially by contact). 



lY. Further experiments with small pellets of filter paper and 

 scraps of indiarubber led to very interesting conclusions. 



We have given a specimen of Actinia a scrap of filter paper about 

 once every 24 hours, placing it on the same tentacles each time. As a 

 general rule, the fragment was carried by the tentacles to the mouth 

 and there very often swallowed, to be ejected as inedible after a longer 

 or shorter period. After a few days, the number varying in different 

 individuals from 2 to 5 days, the fragment is no longer swallowed and, 

 in about another two days, the tentacles will no longer take hold of it. 

 This procedure is more regular in the case of pellets of paper than in 



