INSESSOUES, 81 



Specimens from Tasmania, Swan River, South Australia, 

 and New South Wales present considerable difference in the 

 colour and markings of the plumage, but none, so far as I. 

 have yet seen, of sufficient importance to justify their separa- 

 tion into distinct species : in some the nuchal band and the 

 circular mark on the head are very conspicuous, while in others 

 scarcely a trace of these markings is observable ; these varia- 

 tions do not appear to occur in certain localities only, but are 

 generally found in all. 



Little or no difference is apparent in the size or plumage 

 of the sexes. In all the irides are blackish brown. 



Sp. 39. iEGOTHELES LEUCOGASTER, Gould. 



White-bellied Owlet-Nightjar. 

 JEgotheles leucogaster, Gould in Proc. Zool. Soc, part xii. p. 106. 



iEgotheles leucogaster, Gould, Bh'ds of Australia, fol., vol. ii. pi. 2. 



This is altogether a larger and more powerful bird than 

 the jEgotheles Novcs-Hollandm ; besides which, the white 

 colouring of the lower part of the belly will at all times serve 

 to distinguish it from that species. 



Gilbert states that it is abundant in most parts of the settle- 

 ment at Port Essington, "where it is frequently seen flying about 

 at twilight, and occasionally during the day. On the approach 

 of an intruder it flies very heavily from tree to tree, and on 

 alighting invariably turns round on the branch to watch his 

 approach, moving the head all the time after the manner of 

 the Hawk tribe." 



The White-bellied Owlet-Nightjar feeds on insects ; and as 

 the bird is strictly a nocturne, they are, as a matter of course, 

 procured at night. 



The sexes when fully adult will not, I expect, be found to 

 differ in plumage ; but whether the red or the grey varieties 



