Report on the zoological collections made in the Indo-Pacific Ocean ...

BIRDS. 23shaft-streaks ; ear-coverts dusky brown ; cheeks clear fulvous, withcentral streaks of light brown, breaking up into irregular cross lineson some of the feathers ; throat and fore neck white, with irregularzigzag cross lines of light brown ; remainder of under surface of bodyunder tail-covertsclear fulvous, crossed with zigzag lines of brown ;uniform and deeper buff ; axillarics like the breast and barred acrossin the same manner; under wing-covcrts whiter and crossed distinctlywith blackish bars, broader and forming a distinct patch on themedian lower coverts near the edge of the wing.The above description is taken from a young male shot near PortEssington.An old bird, with more than half his tail-feathers blue, has hisplumage very much abraded and the crest-feathers reduced tohair-like broAvn plumes. The blue ends to the wing-coverts arealmost entirely worn off ; but on the breast he is replacing hisfaded plumage by a clean moult, the new feathers being verybroadly centred with blackish ; the under surface of the body isdirty buff, with brown zigzag cross bars, becoming less distinct onthe throat.Compared with young birds, the old D. cervina are very muchpaler buff below and less distinctly barred underneath, the collarround the hind neck is nearly uniform, with scarcely any remainsof zigzag cross-barring, while the head and crest are white orbuffy white, streaked with brown down the centre of the feathers ;but the whole head is distinctly streaked, instead of being uniformbrown as in the young birds. The cobalt-blue on the shoulders is,of course, much more brilliant and more developed than in theyoung ones.The mode in which the barring on the under surface becomesless and the head more streaked is well shown in an immature malebird, which has the head losing its uniformity for the streakedstage, and yet retains the rufous upper tail-coverts of the immaturestage, while the tail is only half overshaded with blue.The differences between the young and old specimens of Dacelocervinus seem to me perfectly comprehensible ; but the relations ofD. leacMi and D. occidentalis are not so clear. There is considerablevariation in length of wing throughout the whole series.All our specimens of D. leachii have more or less remains of theirold rufous-barred tail, but they are all completing their change tothe uniform blue tail, and consequently the outer feathers are inmore or less irregularly blue-banded stages ; but every proof is furnishedthat the outer feather will become perfectly blue, like thecorresponding stage in D. cervinus, so that the character of the barredouter tail-feather will not hold.Undoubtedly D. leachii is a larger and more powerful bird thanD. cervinus. It is often similarly fulvous on the breast ; but thezigzag bars are coarser and are continued higher up on the throat,as well as being strongly developed on the collar round the hindneck. The older the bird becomes, however, it is evident that, as inD. cervinus, the cross-markings on these parts become more and more