THE BURMO-MALAYAN BUTTON-QUAIL. 1 85 



tions in tint, amount and extent of markings, &c., in this species, 

 can be exactly matched in specimens of jondera and vice versd. 



Therefore the figures of this species may be taken as re- 

 presenting also types of plumage of joudera, while the figures 

 of this latter exhibit types of plumage common to the present 

 species {macidosns) likewise. 



For be it understood that, though there is a marked differ- 

 ence in size, I can discover no other constant difference between 

 the two species. 



If you have two or three specimens only of each, the birds 

 are so variable that the chances are against any one of either 

 corresponding closely with any one of the other ; but if you 

 have, say twenty of each, at least ten of either will be counter- 

 parts of ten of the others, and five will be fairly mat enable. 



The difference in size is great. In the Indian birds the wings 

 of males vary from 3*0 to 3*25, and those of the females from 

 3"3 to 3*55. But unless the birds have been sexed, it seems to 

 me impossible to separate large females of joudera from small 

 males of maciilosvs. Whether, under these circumstances, and 

 having regard to the different geographical areas occupied by 

 the two forms, it is desirable to treat them as distinct species, is 

 a matter of opinion. 



Generally I may say that, so far as I am able to judge, the 

 plumage of the sexes does not differ. The extraordinary varia- 

 tions observable are due, it appears to me, to differences in age. 

 As far as I can make out, the younger birds have the upper 

 surfaces profusely marked with ferruginous red, black, and 

 sometimes more or less of buff on a grey brown ground, and 

 they have only a trace of the rufous collar. Gradually the mark- 

 ings on the mantle grow fainter and fainter, till it becomes a 

 nearly uniform grey brown, not so blue as is depicted in Vieil- 

 lot's figure, but still a somewhat grey brown. As this change 

 takes place, the red collar comes out strongly, as shown in the 

 figure referred to. The spottings on the wings diminish in size, 

 and the markings on the head become brown instead of 

 black. 



On the lower surface, in the younger birds, the sides of the 

 breast are a grey, at times somewhat olivaceous, brown, of which, 

 however, little is seen, as the feathers are broadly tipped with 

 buff and have a large black spot inside this tipping. As the 

 bird gets older, these spottings almost entirely disappear from 

 the sides of the breast, a few only remaining on the sides of 

 the upper abdomen. Vieillot figures an old, but by no means 

 a very old, bird, and in no specimen are the tertiaries, scapulars, 

 and back the blue grey he has depicted them. Had the ground 

 colour of these parts been brown with a grey shade, his picture 

 would have accurately represented some specimens before me ; 

 but, as a rule in birds at that stage, the markings on the head 

 would have been dark brown and not black. 



24 



