310 BIRDS OF AUSTRALIA. 



surprised that individuals exhibiting a change from blue to 

 white or vice versa never occurred. At length, while on 

 Dugong Island, I was convinced they were specifically dis- 

 tinct by seeing that the half-grown young from the nest had 

 assumed the distinctive colour of the parents. This was first 

 pointed out to me by Dr. Muirhead, R.N., whose attention I 

 had previously drawn to the subject. The habits of both 

 species are similar ; and they procure their food in the same 

 manner at low water on the coral reefs surrounding the low 

 islands they frequent. The nest and eggs are precisely simi- 

 lar, but the young of this bird is white from the nest." 



The entire plumage snow-white ; bill yellowish straw-colour, 

 with a dusky tinge on the culmen and towards the point ; 

 irides primrose-yellow ; eyelids bright yellow ; lores and orbits 

 dull greenish ; legs and feet yellowish green ; soles orange ; 

 claws pale horn -colour, hind one dark ; anterior plates of the 

 toes bluish black. 



Genus NYCTICORAX, Stephens. 



Europe, Africa, and America are all inhabited by Night 

 Herons ; consequently they constitute one of the most widely 

 distributed sections of the family. They are nocturnal in their 

 habits, and approximate to the members of the genus Botau- 

 rus, particularly in the laxity of their neck-plumes. The sexes 

 do not differ from each other in theii' colouring, but the 

 young are rendered remarkable during the first year of their 

 existence by their plumage being conspicuously blotched and 

 spotted all over. 



The single Australian species cannot by any possibility be 

 confounded with either of those inhabiting any other part of 

 the world, the cinnamon colour of its back rendering it con- 

 spicuously diff'erent from all of them. 



