226 OX INSECT SOUNDS. 



Instance, when an insect performs any movement in apparent 

 recognition of some sound uttered by its companion, is that 

 movement directed by the insect's consciousness, or does it take 

 place in direct response to the sound heard as a reflex of sensation, 

 whose issue in any particular movement is determined not by effort, 

 of will, but by conditions of the bodily structure ? The experiments 

 to be cited will partly answer this question 5 but I may here remark 

 that the absence of volition is strongly indicated by the fact that 

 an insect does not vary its action according to circumstances, or 

 repeat it from memory as the lasting effect of a long past impression, 

 but only when the impression is repeated. If, on the contrary, an 

 insect does so vary its action, and repeat ic on the motive of 

 subjective sensation, then the act is removed beyond the sphere of 

 reflex function, since we cannot imagine an indefinite prolongation 

 of reflex function. 



It must be granted that insect brains possess faculties 

 proportional to the capacity of their sensory organs. Hence the 

 measure of psychical endowment may be guessed at by close 

 study of the organs of touch, smell, sight, and hearing, and of 

 their relation to the brain ganglia. It must also be conceded that 

 in an insect, as in all animals possessed of adequate organisation, 

 there must exist a proportionate sense of bodily well or ill being 

 which prompts its action. Consequently that the various acts of 

 its life are associated with the conditions of well or ill being 

 imposed on it by external surrounding. But it is quite another 

 thing to assume that pleasure or pain evinced by movements of 

 the body have become sub-'ective, and as such constitute motives 

 of action or reflection on the part of the insect. To aflirm for 

 instance that the surprised cry of alarm is a deliberate vocal 

 utterance intended to warn its companions of danger, or that the 

 song which attracts one insect to another is literally a love speech 

 or a war defiance, instead of an implanted instinct the purport of 

 which reaches beyond its individual life, knowledge, or intention. 



Until the physiology of insect brain has been satisfactorily 



