164 Habit and Instinct. 



How far, if at all, these habits are instinctive, we do not 

 know. The plants which the birds treat in this way 

 are. Dr. Lowe says,* all exotics, so that the habit has in 

 all probability been acquired since their introduction into 

 the Canary Islands. It would seem to be the result of 

 intelligence, and handed on through imitation. 



Another change of habit, probably of intelligent origin, 

 is afforded by the oft-quoted case of the kea {Nestor 

 notabilis) of Middle Island, New Zealand. It belongs to 

 the family of the brush-tongued parrots, and, according 

 to Mr. Taylor White,t lived on the mountains above the 

 forest-line, feeding upon the lichen on the stones. If 

 this was the case, it would seem to be a modification 

 of the normal habits of the family, which usually feed 

 on nectar, insects, fruits, and berries. About 1868 it 

 was observed to attack living sheep. Those which, having 

 missed a shearing, had long wool died suddenly, the only 

 apparent cause of death being a wound far down the back. 

 This was found to be due to the kea, which was, according 

 to Mr. White, attracted to the sheep by the resemblance 

 of the wool to lichens, the spot chosen being due to the 

 fact that it there escaped the efforts of the sheep to 

 dislodge it. The bird's object was to obtain blood; but 

 it may subsequently have found the kidney fat which lay 

 beneath. Whether this curious change of habit is tending 

 to become hereditary and instinctive we do not know. 

 Imitation would presumably be sufficient to account for 

 the handing on of the habit. But the bird is being 

 destroyed by the owners of sheep, and will probably ere 

 long become extinct. 



Mr. Joseph Willcox records a curious habit of the crow 



* Zoologist, vol. xix. 1895. Cp. Wallace's " Darwinism," p. 75. 

 t Froc. Acad. Nat. Sei. Philadelphia, 1877. Abstracted January, 1878 ; 

 noted in Nature, vol. xiii. p. 589. 



