IIYDHOCIIKLIDON. 303 



grasshoppers and other land insects, in fact it may be seen capturing its prey on the land, as on 

 the water, darting down and procuring it in just the same manner. I discovered the breeding 

 place of the Marsh Tern in a swamp overgrown with dwarf Polyi^ouuui bushes. .Vbout a 

 week previously, when riding around the swamp, I was led to the conclusion that these birds 

 nested there, as numbers were flying about above the water, whilst many others were perched 

 on the slender tops of the dwarf Polygoinin: bushes, which projected a few inches above the 

 water; and I also noticed several of the birds flying about were carrying rushes in their bills. 

 I made a careful search at the time, but beyond finding a few green rushes placed in a careless 

 manner on the top of one of the Polvgoninii bushes, I saw nothing else to indicate that it was a 

 contemplated breeding site. On the 31st October, 1899, I observed numbers of the birds on 

 the tops of the bushes, but not :note than one on each bush, whilst numbers were also flying 

 about in an excited manner, and as 1 neared the edge of the swamp kept up a continuous 

 croaking. On wading; in for a closer examination, I found that each bird was sitting on a nest — 

 if nest such a structure could be called — each of which contained from one to three eggs, the 

 latter number apparently being the full set. These nests were simply a few green rushes, in 

 most cases quite flat, and the whole structure rising and falling with the motion of the water, 

 caused by a slight breeze, and it was a mystery to me how the birds managed to leave and 

 return to the nests without throwing the eggs off. Although the swamp is of considerable extent 

 and similar throughout, the breeding place was confined to a space of not more than twenty 

 yards square, showing that, like Stii'ua aii^^lka, they breed in companies." 



On the nth December, 1899, ■^I''- Bennett wrote as follows : — " To-day I passed the swamp 

 in which I obtained the Marsh Tern's eggs at the end of October and beginning of November, 

 and noticed they were in far greater numbers than on the previous occasion, and that they were 

 breeding all over the swamp, and had not only constructed fresh nests, but had utilised the ones 

 from which I had taken the eggs, and also the disused ones of Tribonyx vcntralis and other birds. 

 I examined a great number of nests, all of which contained eggs." 



From Broken Hill, South-western New South Wales, Dr. W. Macgillivray has sent me 

 the following notes : — " Hydrochdidon hyhrida is commonly to be found over the lakes and swamps 

 of South-western New South Wales when conditions are favourable. During the latter part of 

 December, 1903, a large colony of these birds nested on the ' Currant bushes ' growing in the 

 shallower part of North Yellow Lake, Topar Station, about fifty miles from Broken Mill. The 

 nests were substantially built of sticks and twigs, lined with grass, and well above the water 

 level ; there were about one hundred and fifty nests in all, and, curiously, at the foot of nearly 

 every bush was a nest of the Black-throated Grebe. A few days after heavy rain rose the level 

 of the water above that of the nests, and destroyed the whole colony. They did not nest again 

 in such numbers, as on the 31st of the following month I found only a few nests around the 

 margin of the lake; these each consisted of the trampled down centre of a bunch of fine rushes, 

 no other material being used. Most of the nests on this occasion contained clutches of three 

 eggs, m an advanced stage of incubation. A month later, on Inkerman Lake, on the same 

 station, I again found them nesting, their nests consisting only of a little heap of floating water 

 weed on water five to six feet in depth, the surface of the water being covered with weed; it 

 was amusing to watch the newly hatched young crawl away from their nests and flatten them- 

 selves on the surface of the water, being extended in like manner to a young Plover on land. 

 Unlike the Gull-billed Tern, this species hunts for food over the water, and is nearly always 

 observed in small flocks. 



Writing in May, 1913, Dr. Macgillivray remarks : — " When we visited North Yellow Lake, 

 on Topar Station, on the 15th of December, 1912, we found a number of Marsh Terns (Hydro- 

 chelidon hybrida) ' hawking ' over the lake in company with many Gull-billed Terns. At Silistria 

 Lake, on this date, several Marsh Terns were noted settling on the water weed, and flying about. 



