368 THE ANIMALS OF NEW ZEALAND 



As to the reason for the bell-hird's song being pitched in a 

 higher key, it may perhaps be found in the fact that thick mists 

 often envelop the mountain's side, that the bushes in the more 

 elevated gullies are much scattered, small, and isolated. Hence 

 the alpine note is fitted to meet the peculiar physical conditions of 

 certain localities, by enabling the sexes to communicate with each 

 other when collecting food at some distance apart. 



The power of imparting intelligence, as exercised by birds, 

 nmst be obvious to anyone who is acquainted with the ordinary 

 inmates of a poultry-yard. In many feral species that have 

 come under observation, this faculty is quite as conspicuous as it 

 is amongst many domesticated proteges. One summer, for the 

 first time, a few tuis appeared amongst the cherry trees in a 

 garden up the gorge of the Ashburton, miles away from any 

 wood frequented by the tui ; for the first time cherries were 

 tasted, and the knowledge of their excellence was communicated, 

 and the trees stripped by the industrious tuis. Not a very great 

 time ago. when slowly sailing up the harbour, one of the 

 children threw a piece of bread to a young gull (L. dominicanus) , 

 the only bird in sight. Its bark of pleasure brought others, till 

 then unseen, and the wake of our boat was enlivened by an 

 irregular train of noisy attendants. Those species which do not 

 launch lightly in the air when taking flight, I believe, may be 

 ranked among the more silent birds, as, for instance, the 

 cormorants ; birds of the genus seem to need a fulcrum to rise 

 upon the wing. The fleet kingfisher, too ; when its perch is a 

 bough, and it leaves it to dash at its prey, the bough may be seen 

 to vibrate for some time after it has been quitted. Both of these 

 genera may l)e fairly classed with the non-vociferous tribes, not- 

 withstanding that the Halcyon indulges in a variety of expressive 

 notes during the ])reediug season. 



I now leave with regret the interesting study of bird sounds, 

 and trust that others will prosecute further observations, for 

 there is nnu-h to be learnt by the field naturalist about their notes 

 and calls, which would assist in revealing many interesting points 

 in the history of the fauna. 



