CH. TV.] ANIMAL LIFE. 835 



organs, even when these are not directly irritated, and act as 

 though they were felt, is shown by the fact that the fluttering 

 of the wings, whereby the female butterfly allures the male to 

 sexual congress, irritates the nerves of the decapitated male 

 butterfly generally, and not those of the sexual organs in par- 

 ticular, as any other fluttering would ; yet it has the same 

 eff'ect on the sexual organs of the male as if they felt it, and it 

 was reflected as a conceptional internal impression. It is 

 shown, however, that this reflexion of the external impressions 

 on the sexual organs, purely by means of the vis nervosa, takes 

 place for the first time at this period of propagation, and be- 

 cause the route thereto is as it were laid down, from the fact, 

 that the external impressions made by the fluttering of the 

 female on the decapitated male butterfly, are not thus reflected, 

 unless they have copulated at least once before decapitation 

 (560). 



656. The internal impressions caused by conceptions in sen- 

 tient animals, or independently of conceptions in the insentient, 

 manifest, at this period, the same new powers of action on the 

 sexual organs as external impressions. The remembrance of 

 a sensation, that in the child would excite no attention what- 

 ever to sexual congress, now becomes a sensational excitant of 

 the instinct, and it is probable that the mind repeats the for- 

 mer pure sensation, increased by new sub-impressions [Merk- 

 male] that excite this new instinct, and from which the former 

 sensation was entirely free. This also appears to be imitated 

 in insentient animals by the vis nervosa, when the female of 

 insects, if decapitated at the period of sexual excitement, not 

 only continue the sexual functions, without any apparent ex- 

 ternal excitement, but frequently recommence them after a 

 period of repose, fluttering with their wings, to call as it were 

 the male to sexual congress. 



657. In reasoning animals this period of life is not distin- 

 guished by all these new movements in the vis nervosa and in 

 the cerebral forces, as is the case in sensational animals, but 

 the understanding and will attain to new and higher powers. 

 Every one is aware that these attain the greatest perfection 

 of which they are capable, with adult age. The brain also 

 acquires a higher and more perfect development, in accordance 

 with the greater perfection of the mental powers. 



