r ■ 



SULPHUR PARRAKKET. 429 



of the opposite colour, as Ravens, Magpies, Black- 

 birds, &c. There are also white varieties of 

 Thrushes, Jays, Partridges, Snipes, and Wood- 

 cocks, Sparrows, Swallows, Martins, and Goat- 

 suckers. It has been imagined that such changes 

 were owing to age; but, on the contrary, it is 

 certain that these variations from the genuine 

 colour are always observed to take place in young 

 birds or nestlings, and these birds at their first 

 moulting sometimes recover, either wholly or in 

 part, their proper colours. Neither is this change 

 confined, as is often supposed, to the birds of 

 Northern Climates, but takes place equally in those 

 of Africa and South- Am erica. There is however, 

 adds Monsr. Levaillant, no example of any kind 

 of the Parrot tribe becoming white or varied with 

 white, (exclusive, of course, of the Cockatoos,) 

 which are naturally of that colour. We frequently 

 however observe several of the Parrot tribe to be- 

 come patched with yellow, and even to become 

 entirely of that colour, however different their na- 

 tural plumage may have been. We find that 

 throughout Nature yellow forms the base of green^ 

 which is the prevailing colour in the Parrot tribe. 

 Thus the leaves of trees, when fading, or dried, 

 turn yellow. This colour also, according to Monsr. 

 Levaillant, is the basis of red; and from the whole 

 he concludes that yellow is to the Parrot tribe what 

 white is to the generality of birds. 



To return to the individual above described, or 

 Sulphur Parrakeet, Monsr. Levaillant considers it 

 ;as most allied to the Rose-Ringed Parrakeet, of 



