PACKARD] MENTAL POWERS OF INSECTS. 3C7 



bee (Xylocopa violacea) gained access in a similar manner 

 to the nectar of Antirrhinum Linaria and majus and Mirah- 

 ilis tTcdappa ; as do the common bees of the Isle of France 

 to that of Canna nidica; and I have myself more than once 

 noticed holes at the base of the long nectaries of Aquilegia 

 vulgaris, which I attribute to the same agency." 



Another instance of change of habit by the individuals 

 of a species is afforded in the same work ; we quote the fol- 

 lowing statement from Sturm. "It is the instinct of Geo- 

 trupes verncdis to roll up pellets of dung, in each of which 

 it deposits one of its eggs ; and in places where it meets 

 with cow- or horse-dung onl}-, it is constantly under the 

 necessity of having recourse to this process. But in dis- 

 tricts where sheep are kept, this beetle wisel}^ saves its labor, 

 and ingeniously avails itself of the pellet shaped balls ready 

 made to its hands, wdiicb the excrement of these animals 

 supplies." 



Another instance where choice is made between two alter- 

 natives is stated by Mr. Darwin. In liis "Origin of Spe- 

 cies" he gives the following account. "One of the strongest 

 instances of an animal apparently performing an action for 

 the sole good of another, with which I am acquainted, is 

 that of aphides voluntarily yielding, as was first observed 

 by Iluber, their sweet excretion to ants ; that they do so 

 voluntarily, the following facts show : I removed all the ants 

 from a group of about a dozen aphides on a dock-plant, and 

 prevented their attendance during several hours. After this 

 interval, I felt sure that the ai)hides would want to excrete. 

 I watched them for some time through a lens, but not one 

 excreted ; I then tickled and stroked them with a hair in the 

 same manner, as well as I could, as the ants do with their 

 antennae ; but not one excreted. Afterwards I allowed an 

 ant to visit them, and it immediately seemed, by its eager 

 way of running about, to be well aware what a rich Hock it 

 had discovered ; it then began to play with its antenniu on 



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