220 Mr. A. Anderson on the Nidification 



because the cause or causes of their evolution were identical 

 or nearly identical ? and thus a considerable number of sup- 

 posed changes in the level of many countries, of which we do 

 not find geological records, can be dispensed with. 



It is true that instances to be explained by the migration 

 or accident theories are of more frequent occurrence and more 

 easily proved ; but I think it would be just as interesting, 

 where these cannot be admitted, to trace in all its bearings 

 the similitude of species in distant countries. This view 

 would, at least, open up a field of fresh research, and aflFord a 

 new illustration and confirmation of the great theory of evo- 

 lution. 



XXVI. — On the Nidification of certain Indian Birds. — 

 Part III,^ By Andrew Anderson, F.Z.S. 



The Nukta or Comb-Duck [Sarkidiornis melanonotus) , the 

 Whistling Teal {JDendrocygna arcuata), and the Cotton-Teal 

 [Nettapus coromandelianus) are non-migrant, and breed 

 throughout the plains of India during the " rains," viz. from 

 July to September, according to locality. 



These Ducks, according to my experience, nest almost ex- 

 clusively on trees ; and they are, so far as nidification is con- 

 cerned, essentially perching Ducks. They begin to pair early 

 in June, and may be seen flying about in search of a suitable 

 tree almost simultaneously with the first fall of rain, which 

 generally occurs in the north-western provinces on or about 

 the 18th of that month. 



Sarkidiornis melanonotus. 



This curious and handsomely coloured Duck deposits its 

 eggs in holes of old deciduous trees, and never, I should say, 

 '' in grass by the sides of tanks &c.,^' as stated by Jerdon. 

 The male bird (as in fact do all the others) assists the female 

 in the selection of a site. I have frequently watched both 

 birds flying into trees together, the male uttering a harsh 

 grating noise, while his mate is left behind on inspection 

 duty. 



* For Part II. see Ibis, 1873, p. 74. 



