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 afford a 
new illustration and confirmation of the great theory of evo¬ 
lution. 
XXYI.— 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 (. Dendrocygna 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. 
