HYDROCHELIDON HYBRIDA. 
999 
estuary, they take their course close above the surface of the water, not deviating from the direction they have 
resolved to travel in. Their note is a shrill and not unpleasant little scream, sometimes varied by a hoarser 
cry, and which they utter very frequently when congregated in some spot supplying them with an abundance 
of food. They consume very small fish and aquatic insects, as well as worms and various larva;, and never by 
any chance alight of their own accord on water. 
Nidification . — Though I was not fortunate enough to find the eggs of this Tern, I am under the impres- 
sion that it breeds to a limited extent in Ceylon. I met with a flock one evening at Topare tank m the month 
of July, which flew in from the surrounding country and settled in the middle of the morass ; and though I 
was near enough to see that some were in winter plumage as they passed, I think others were m breeding-livery. 
At Kanthelai I have shot them in the latter plumage in August. In India they breed in June and July, resorting 
to large jheels and swamps, and building loose nests of rush-stems and reeds on floating vegetation. The late 
Mr. A. Anderson, who discovered a breeding-colony at Fyzabad (Oudh), situated in a swamp, which is 
described as a tangled mass of weeds and aquatic plants, observed the birds carrying long, wire-like reeds some 
2 feet in length. “ The circumference,” he writes, “ of some of the nests I measured ranged between 3 4 and 
4 feet, and they were about 4 inches thick. They were composed entirely of aquatic plants, and so inter- 
woven with the growing creepers that it was impossible to remove them without cutting at the foundation of 
the structure.” The eggs were two and three in number; in another instance, recorded by Mr. Hume, nests 
were found containing only one egg. This author gives the average size of forty-eight Indian specimens as 
1-51 by 1-09 inch. A fine series which I have examined in Mr. Dresser’s collection are oval in shape, some 
rather stumpy at the small end, others compressed, having an ovate pyriform appearance. The shell is smooth, 
without any gloss, and the ground-colour is mostly dull olivaceous or pale olive-grey ; but some specimens are 
brownish stone. The markings consist of large blotches of brownish black or very deep sepia, or small spots 
of the same, pretty thickly diffused over the egg; some are closely blotched with smeary markings of a lighter 
hue, and in others these take a straggly form. In one specimen of the series before me, in the collection of 
Mr.' Dresser, the markings are collected on the obtuse end ; the underlying coloration is inky grey or pale 
purplish grey. The dimensions of several eggs are 157 by 1'13, 1’53 by 1-12, 1"57 by 1Y6, and 1'55 by 
1*33 inch. 
