VISCOUNT WALDEN ON THE BIED8 OP CELEBES. 61 



I have compared two Macassar male examples collected by Mr. Wallace with a large 

 series of Javan individuals, and have failed in detecting any valid specific differences. 

 The black-naped Orioles, before attaining their full plumage, pass through a stage 

 wherein the two centre rectrices retain the olive-green hue found in younger birds, 

 while they have already put on the black feathers which surround the head, and the full 

 bright adult yellow plumage of the entire under surface, the crown, the neck, and the 

 rump, the plumage of the back alone showing immaturity by traces, more or less, of 

 dingy greenish-yellow. It would seem that the central pair of olive-coloured rectrices 

 are not moulted and replaced by a pair of new black feathers, but rather that the olive- 

 green hue changes gradually into black, commencing from near the tips, which are pure 

 yellow at the earliest stage, and thence passing upwards. In adult Javan examples the 

 lesser wing-coverts are tipped with yellow, thus forming a conspicuous yellow speculum. 

 But in Javan examples in the stage of plumage above described, these yellow tips are 

 frequently absent, or only commencing to be developed. The two Macassar examples 

 are in the intermediate stage of plumage described above : one has no yellow tips to 

 the lesser wing-coverts ; in the other they are just appearing. Whether in perfect 

 plumage the yellow alar bar is wanting, as in the Sula B. frontalis, has yet to be ascer- 

 tained. In the mean time I shall retain the Macassar Oriole under the title of the Javan 

 bird. The Macassar species is somewhat larger. Wing 5f, tail 4-f- , bill |-. 



The only Menado example I have been able to examine is in the intermediate stage 

 of plumage, with green middle rectrices and no alar bar. It differs in that the black 

 coronal ring does not unite at the nape, the yellow of the crown being thus confluent 

 with that of the nape. As indications of the complete black circle in Broderipus 

 appear in the earliest stages of plumage, this break in the coronal ring cannot be a 

 sign of nonage. The dimensions differ from those of the southern form. Wing 5f, 

 tail 4f , bill f. It possibly represents a distinct species. 



TUEDIDtE. 



Geocichla, Kuhl. 



67. Geocichla erythronota, Sclater, Ibis, i. p. 113, "Macassar" (1859). (PI. VI. 

 fig. 2.) 



Hab. Macassar (Wallace). 



This species and G. interpres (Kuhl) form a section of the genus which perhaps 

 deserves a subgeneric title. 



Turdus avensis, J. E. Gray, Griffith, Anim. Kingd. Birds, i. p. 530, pi. — , named from 

 an Indian drawing, is either G. interpres or else an unknown Burmese representative 

 form. 



