Some Punjah River Birds. 
69 
small. The general effect (on a smaller scale) being as if 
the blade oi a small table knife wei'c placed along the back 
of a large table-knife, both knives being in the same plane, 
and their hilts together. 
The purpose of this curious development is seen when 
<he birds are feeding, for they fly along with a steady flapping 
gait, often several together, with the lower mandible cutting 
thi'ough the water like the prow of a ship, and this they do, 
either pursuing a straiglit course, or continuously iK'ating up 
wind and then circling round to beat up again over the 
patch of water. 
A small point but one not without interest arises here: 
the figure in Vol. IV., p. 296 {loc. cit.)* depicts the bird 
skimming with the beak closed; yet I have observed it with 
the mandibles wide open. Doth the bird skim in both ways? 
and if so,— what is the difference in effect to the bird? The 
reason of this highly specialised bill and method of feeding 
is apparently unknown, but a yellowish oily fluid is stated 
to be often found in the stomachs of birds examined, and it 
seems reasonable to surmise that this is some floating sub- 
stance which is skimmed from the surface of the wate)'. On 
one occasion I found fish scales in the stomach of a bird shot 
for my collection, and small fish have been reported. 
Another curious feature in the bird is its exti'eniely 
long wings, which give it an ungainly looking f;ai)ping flight, 
whicl will identify it (if seen) at a great distance, but I have 
often noticed that the colouration of the species-- black abovej, 
white below— renders it almost invisible even at moderate 
distances. They have a loud harsh cry, most peculiar in 
character. 
In the Northern Punjab the species appears to be a 
summer visitor only, arriving in March and leaving about 
the middle of August. The eggs are laid early in May. 
The nest is a mere hollow in the sand similar to that 
of t^levna seena, without any addition of material; but the 
eggs are as a rule very different, some approaching in 
colouration to the purple blotched eggs of the Sooty Terns. 
Th(- ground colour varies in tint from pale buff or stone 
colour to greenish or greyish white; with streaks, spots, 
and often large blotches of dark brown, and pale inky purple. 
* " FauMP of Briiish India." 
