110 MARVELS OF TOND-IJ I- ]-;. 



its brain had been removed.* 



It must not, however, be assumed that the ])rain 

 of insects has nothing to do with their movements. 

 It is the means of co-ordinating or directing them 

 to a common end, and gives rise to what are called 

 consensual motions, that is, movements which are 

 accompanied or stimulated by a sensation, although 

 not controlled by a Avill. In man these actions 

 are frequently exhibited, "as when laughter is pro- 

 voked by some ludicrous sight or sound, or by the 

 remembrance of such at an unseasonable time."f 

 Sneezing is another instance of a sensation leading 

 to certain motions, without any intervention of the 

 human will. 



Speaking of these consensual actions, I)j\ Car- 

 penter observes, "It is probable, fi'om the strong 

 manifestations of emotion, exhibited by many of 

 the lower animals, that some of the actions which 

 we assemble under the general designation of in- 

 stinctive are to'^be referred to this group." 



A special volume would be required for anything 

 like a complete '^examination of the little which is 

 known on this subject, but these few^ remarks may 

 assist the microscopic beginner in examining the 

 movements of his subjects, and guard against the 

 error of referring to reason and volition those which 

 are, probably, either the direct result of stimulants 



* Carpenter's Manual of Physiology, p. 551. f Ibid, p. 543. 



i 



