THE HACKLED GROUND-PIGEON. 299 



Subfamily CALCENIN.E. 

 Genus CALGENAS, G. E. Gray. 



659. CALCENAS NICOBABICA. 



THE HACKLED GROUND-PIGEON. 



Columba nicobarica, Linn. Syst. Nat. i. p. 283. Caloenas nicobarica, ////;///-, 

 8. F. ii. p. 271 ; id. Nests and Eggs, p. 510 j Bl. B. Burm. p. 147 ; Hume fy Dav. 

 S. F. vi. p. 425 ; Hume, S. F. viii. pp. 68, 110. 



Description. In the adult the entire tail and longer lower and upper 

 tail-coverts are pure white ; the entire head and neck all deep slaty grey, 

 blackish slaty or even blackish brown in some ; from the base of the occi- 

 put and the whole back of the neck stream down a thick bunch of narrow 

 hackles, those from the occiput more or less disintegrated and hair-like, 

 while those from the base of the neck are more regular feathers ; the former 

 entirely dark slaty grey, the latter metallic green shot with gold and copper 

 and margined everywhere with this slaty grey ; the whole of the rest of the 

 upper plumage, excluding the tail and longer upper tail-coverts, is reful- 

 gent with metallic reflections. The lesser coverts immediately along the 

 ulna and at the carpal joint, the outer webs of the primaries, winglet and 

 greater coverts, the earlier secondaries and their greater coverts are glossed 

 with a deep blue ; the rest of the secondaries and their greater coverts, 

 most of their median coverts, the rump and shorter upper tail-coverts 

 brilliant green, like the speculum of a drake's wing, but with more or less 

 of golden or bronzy reflections in some lights ; scapulars, interscapulary 

 region, lesser and median coverts adjoining the scapulars similar, but with 

 a much stronger coppery glow. This fairly represents the general distri- 

 bution of colours ; but some birds are altogether greener, and some are 

 altogether more coppery ; and the colours of the feathers vary in every light, 

 and it is as difficult to convey in words any adequate description of the 

 ever-changing tints of this bird as it would be to paint the sparkle of a 

 diamond. The upper breast is the same colour as the head ; but even here, 

 if the feathers are lifted, it will be seen that inside the broad slaty grey 

 tippings there is a broad patch tinged with metallic green ; and the lower 

 breast, abdomen, sides, flanks, vent and a few of the shortest under tail- 

 coverts are all variegated deep metallic green and blackish slaty, the latter 

 colour being confined to a terminal fringe to each feather. The first two 

 primaries almost entirely want the blue metallic gloss ; and these, together 

 with the inner webs of the primaries and secondaries, their entire lower 

 surfaces and their longest lower coverts, are blackish brown. The rest oi 

 the wing-lining and the axillaries are a brighter or duller metallic green ; 



