HYDROCHELIDON FLU VIATILIS, Gould . 
Marsh Tern. 
Hydrochelidon Jluviatilis, Gould in Proc. of Zool. Soc., Part X. p. 140. 
Like the European species of this form, the Hydrochelidon nigra and H. leucopareia, the present bird is a 
denizen of inland waters rather than those of the sea-coast, and wherever waters of any extent have been 
discovered in the interior of Australia, it has been found enlivening the scene. I myself observed it in the 
reaches of the rivers Mokai and Namoi, and both Sturt and Hume mention it as frequenting those parts of 
the country visited by them ; I have also seen specimens from Swan River, which do not differ from those 
killed by myself in New South Wales ; it is evident therefore that it enjoys a wide range, and it is doubt- 
less spread over every part of the country wherever marshes and lagoons occur. Its chief food consists of 
aquatic insects of various genera and small fish, which it procures after the usual manner of the Marsh 
Terns, by hunting with scrutinizing care over the surface of the water. 
The breeding-place of this species has not been discovered, but in the particulars of its nidification it 
doubtless closely resembles its congeners mentioned above, which we know breed among the sedgy herbage, 
making a nest just above the surface of the water. 
Little or no difference is observable in the sexes ; they may be thus described : — 
Forehead, crown and nape deep black; all the upper surface, wings and tail light grey ; sides of the face 
and the throat white, gradually deepening into grey on the chest, and the grey into black on the abdomen 
and flanks ; under surface of the shoulder and under tail-coverts white ; irides black ; bill blood-red ; feet 
light blood-red. 
The figure is of the natural size. 
