16 ARKIV FÖR ZOOLOGI BAND 2. N:0 9. 



51. Columba casiotis Bonap. 



cfo^ -3/4, 1/5, 9 1^/4, 2^/4, juv. ^/s 1902 Baimgol. 

 The young bird has no light patches on the neck. 



52. Columba rupestris Bonap. 



ö^ 1^/8 1902 Baimgol, ? ^/ö 1902 Chantengri; 1 juv. ^ji 

 1902 Chantengri, 2 juv. ^''js, ^^/s 1902 Baimgol. 



These specimens probably represent the subspecies pallida 

 KoTSCH. & Hart., but I am not quite sure about this as T 

 ha ve no material for comparison. 



53. Columba intermedia Strickl. 



cfcf 5/8, 10/8 1902 Baimgol, ?? '''/s, ^o/s Baimgol. 



These specimens are all of them true C. intermedia having 

 the rump slate-blue like the back, but three other specimens 

 show a very interesting intergrading to Cohimha livia. The 

 first of these has the rump still slate-blue but| of a much lighter 

 shade than the back. It is a cT shot ^"/s at Baimgol. The next 

 specimen a 9 shot ^^/s 1902 at Baimgol has a still lighter rump, 

 almost white with a shade of sia ty bluish. The third a cT shot 

 15/8 at the same locality might just as well be termed C. livia, 

 as the rump is pure white with a very slight bluish tinge. 

 These three specimens are all of them smaller than the typical 

 intermedia from the same locality and have wings measuring 

 222 — 227 mm., while the wings of the typical intermedia 

 measure 242. The specimens with lighter rump appear to be 

 younger than the others. The last mentioned for instance is 

 in moult and all the feathers of the neck t hat are glossy are 

 either quite new or only partly developed. The second of the 

 light-rumped specimens does not show any gloss on the feathers 

 of the neck, and the first and comparatively darkest is the glos- 

 siest. This seems to indicate that the young specimens of 

 C. intermedia have whiter rump than the adult. But if this 

 is the case, it is evident that the form that represents a 

 juvenile stage of another is the older of the two. Thus should 

 in this case C. livia be the older and C. intermedia the younger 

 or »higher» form which is just the reverse to what Salvadori 

 expresses as his opinion in Cat. Birds. Brit. Mus. Vol. XXI, 

 p. 255. 



