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view which I was at that time led to adopt, that this power is due 

 to electrical influence. 



In the communication alluded to, the idea of these creatures 

 being electrical, was based on the fact, that when the nerve of a frog's 

 limb, prepared after the manner of Matteucci's galvanoscopic frog, 

 is seized by the tentacles of an actinia, contractions of the muscles 

 promptly ensue. It was admitted, however, that all attempts to 

 produce deflection of the galvanometer-needle had failed, and this 

 being the very doubtful state of the question, I ventured to look 

 forward to the pleasure of making another communication on the 

 subject when I had had further opportunities of examining the 

 Actiniae in health and vigour. 



I have now had these opportunities, and have found that the 

 most delicate electrometers are unaffected by these animals, and I 

 conceive that by the following simple, and indeed obvious experi- 

 ments, all idea of the Anemones of our coasts being electrical may be 

 set aside. 



A galvanoscopic frog's limb having been prepared, with the nerve 

 as long as possible, it is laid on a piece of perfectly clear glass, so that 

 the nerve hangs over the edge. The pendent nerve is lowered into 

 the water containing an Anthea, and the nerve is brought in contact 

 with a single one of the long tentacles of this creature ; immediately 

 vigorous contractions follow in the muscles of the limb, and if 

 everything be left undisturbed, these twitchings will continue for 

 some minutes after the nerve is withdrawn. 



If, however, a thread be tied round the nerve, below the point 

 where the tentacle of the Anthea had touched it, all twitchings at 

 once cease. If the portion touched by the tentacle be snipped off, 

 all twitchings also cease. Having thus repeatedly observed that 

 contact between the nerve and a single tentacle was followed by 

 muscular contractions, which at once ceased as soon as the portion 

 of the nerve which had been in contact with the tentacle was 

 removed, it occurred to me to try the effect of applying to the 

 nerve a single tentacle removed from the body of an Anthea. I 

 therefore had recourse to the following experiment : The hind leg 

 of a frog is separated from the body, the sciatic nerve dissected out 

 carefully, so that the nerve be not crushed or injured, and the thigh 

 cut away. The limb with the nerve thus dissected out as long as 



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