Uniform Standard for Comparative Animal Psychology. 131 



and the perfection of the inner senses, of the sensile 

 memory, of the sensile imagination and appetite de- 

 pends on the relative development of the brain. 



Now, it is undoubtedly true that the centralization 

 of the nerve apparatus even of bees and ants is inferior 

 to that of dogs or simians. This is particularly ap- 

 plicable to the connection of the abdominal ganglia with 

 one another and with those of the thorax, a connection 

 which is effected only by a tender double longitudinal 

 commissure. It is the probable cause of the greater 

 frequency of mere reflex motions in insect life than in 

 that of higher mammals ; it accounts for the less perfect 

 unity of sensitive consciousness in insects, manifested 

 by such facts as that of the ant which continues to 

 struggle even after the loss of its abdomen, or that of 

 the bumble-bee which does not cease to suck honey after 

 being deprived of its abdomen, or that of a dragon- 

 fly which bites off her own abdomen, when it is bent 

 forward and thrust between her jaws. According to 

 Ch. Janet's conscientious observations 1 one can even 

 cut off the abdomen of a hornet in the act of sucking 

 honey, without disturbing the occupation of the animal 

 in the least. The fact that any lesion, the loss of limbs 

 or of such parts of the truncus, which are more remote 

 from the head, mostly causes only slight changes in 

 the immediate activity of articulate animals, suggests 

 that very little pain is connected with such lesions, and 

 the slightness of the pain argues the imperfect unity 

 of sensitive consciousness and consequently an inferior 

 degree of centralization of the nervous system. 



It is true, great precaution is needed in identifying 



*) "Sur Vespa crabro" (Mem. Soc. Zool., France, 1895), p. 104. 



