[Chap. V, 18 



I'AEAS. 12, }'3& U.l 



"A theory lias ]iee;i advanced," sr/?/,<! Fnn?, " to the 

 effect that different markings on th<^ wings of allied birds 

 are ' recognition marks ' wlicroby ilio individuals of each 

 species are enal)led to know tlicir own kind, and hence 

 verify the proverb about birds of a fcatlier sticking 

 togetlier. Nevertheless tlie Ducks which furnish such 

 excellent examples of differing wing-markings, also furnish 

 . evidence which is rather unfavourable to this recognition- 

 colour idea. In the first place, several of tlie Pocliards 

 ajiree in havino- the same wing-pattern, and tlie tlight 

 of these is certainly not quite the same. And, secondly, 

 the wing bar is not alnnys constant in the same species in 

 all its individuals. The female Wigeon seldom has one, 

 and it is generally absent in tlie female Pintail, though 

 I knew at one time in Tndia of no less than three female 

 individuals of this species which acquired it, though 

 witliout it at first. Also the female G-arganey gets an 

 approach to this marking wdth advancing age ; so that it 

 would seem that these two species are now acquiring the 

 marking, which is not yet fixed." 



One parts from the "recognition mark " theory with 

 reoret. Tt seems to help to explain the wonderful preci- 

 sion of the movements of the flocks and the time they 

 keep. But, points out Finn, if it were so important to the 

 birds to know each other, the slower, w^eaker females would 

 need to show their nationality more than the males, the 

 more so as they are the members of the species which are 

 so difficult to distinguish as to render a special recognition 

 mark necessary. Finn inclines to the conclusion that nature 

 intended the marking as an ornament, as indeed it is. " It 

 is in some cases at any rate," he says, "displayed in court- 

 ship, and that no doubt is the chief use of its presence." 



Residentsand ^^- Only one of the thirteen, vis , the Spotbill, is a 



migrants. common resident breeding in Upper India, a fact of interest 

 to the gunner because the bird has not the same dense 

 plumage as those that come to India from colder climes 

 and does not accordingly carry as much shot as other duck 

 of equal weight. The Marbled Duck is not known to 

 breed in Sind, but is probably of limited migration. 



ThrouiihoiU the winter, a got'Jd deal of movement 

 goes on within India. Thus, before Christmas, the sports- 

 man in the Western Panjal) may be shooting, besides 

 the pretty constant Shoveller, (iadwall and Common Teal, 

 mostly White-eyed and (laterj Aiallard while, after Christ- 

 mas, on the same water the birds may be mainly Mallaid, 

 e.g., The Pochard, the White-eye and the Tufted Duck. 

 Local, not less than complete seasonal, migration depends 

 on food supply. 

 Dates of 14. It may be of interest to taluUate (see below) (the 



arriv.il and ai)iiroxiiuate dates of arrival in and departure from the 

 departure. ^ ^ ^ 



