332 SEA-SIDE STUDIES. 



much care as others * Such facts might easil}; be multi- 

 plied. Looking at these, however, we are forced tio conclude 

 with Unzer, that "it cannot be inferred from the j)ccurrence 

 of those movements which usually accompany an external 

 impression, particularly tickling or smarting, that the latter 

 are felt, but only that there is that present in the external 

 impression which can cause tickling or smarting. If an 

 acephalous foetus, or the headless trunk of a worm or insect, 

 be irritated, the same movements result as would have been 

 considered the direct and incidental sentient actions of the 

 irritation if it had been felt. If it be so irritated that pain, 

 under ordinary circumstances, would have been caused, then 

 those movements result which are the ordinary direct and 

 indirect sentient actions of pain. The injured pait con- 

 tracts, is congested with blood, swells and inflames, and the 

 animal writhes, tries to escape, leaps, flies, defends itself, 

 and exliibits all the signs of suflering although it is inca- 

 pable of sensation." f 



It thus becomes evident that shrinking, struggling, cry- 

 ing, &c., are no certain indications of pain. Nay, if we 

 were to accept the shrinking as evidence, we should be 

 forced to admit that the flower feels pain when it shrinks 

 on being touched. The other day I was dissecting a Solen, 

 which had already been dead eight-and-forty hours, and 

 was beginning to decompose, yet no sooner did the scalpel 

 touch the muscular foot, than that foot shraidi, as it would 



* Unzer : Principles of Phjsiologi/ (ti-ans. by the Ray Society), p. 213. 

 t Unzer : loc. cit., p. 233. 



