406 BIRDS OF AUSTRALIA. 



required to fancy that so light and delicate a body must be 

 tenanted by some wandering fairy spirit." 



The sexes do not differ from each other in outward 

 appearance. 



The entire plumage is snow-white ; bill dark blue at the 

 base, black at the tip ; irides black ; feet orange. 



Genus HYDROCHELIDON, Boie. 



The members of the present genus inhabit inland waters 

 and marshes, make their nests among the rushes, and lay 

 strongly-marked eggs, in which they differ from the other 

 Terns, the generality of which deposit their eggs on the 

 shingles of the sea-shore. 



Sp.610. HYDROCHELIDON LEUCOPAREIA. 



Marsh-Tern. 



Sterna hyhrida, Pall. Zoog. Rosso- Asiat., torn. ii. p. 338. 



leucopareia, Natt., Temm. Man. d' Orn., 2de edit., torn. ii. p. 746. 



delamoita, Vieill. Ency. Meth. Orn., part i. p. 350. 



leucogenys, Brehm. 



Viralva leucopareia, Steph. Cent, of Shaw's Gen. Zool. vol. xiii. p. 171. 

 Hydrochelidon hybrida, Bonap. Compt. Bend, de I'Acad. Sci., torn. xli. 

 fluviatilis, Gould in Proe. of Zool. Soc, part x. p. 140. 



Hydrochelidon fluviatilis, Gould, Birds of Australia, fol., vol. vii. 

 pi. 31. 



The present bird, which I figured and described in the 

 folio edition as Hydrochelidon fluviatilis, but which I now 

 believe to be identical with H. leucopareia of Europe and 

 India, is a denizen of inland waters rather than those of the 

 sea-coast, and wherever lagoons of any extent have been dis- 

 covered in the interior of Australia, ii has been found enliven- 

 ing the scene. I frequently observed it in the reaches of the 

 rivers Mokai and Namoi, and both Sturt and Hume mention 



