164 THE USEFUL BIRDS 



SPOTTED NIGHTJAR, 



Eiirostopus argiis, Hartert. 



U-ros 1 -p us dr'g n s. 

 Eurus, wide; osteon., bone; jjous (podos), foot; Argus, hundred -eyed. 



EuEOSTOPUS ARGUS, preserved and mounted specimens in the States' 



Museums. 



Geographical Distribution. — Areas J, 2, 3, 4, 6, 7, 8. 9. 



Key to the Species. ^ — Freckled grey and brown ; large white patch at 

 side of neck ; abdomen and under tail coverts ^^niform rusty- 

 brown ; mouth is deeply cleft and gape is very wide ; wing less 

 than 9 inches, tail 6J inches. 



Four species of these nocturnal birds are to be found in 

 Australia. It is remarkable that in the case of two species — 

 the one under consideration and E. alhigularis — the plumages 

 vary with the nature of the soil amid which the birds live, and 

 there is so strong a likeness in the two that, according to Mr. 

 Hartert, an English nomenclator, for purposes of identi- 

 fication measurements only can be taken as a safe guide. 

 The wings of the Spotted Nightjar are less than 9 inches in 

 length, whilst in the case of E. alhigularis they are more than 

 9.5 inches. 



A third species is Caprimulgus mucrurus, Hors., dis- 

 tinguished by having the four outer primaries spotted white' 

 and the wing 7J inches in length. The fourth species is the 

 Owlet Nightjar, specially referred to on the following page. 

 In appearance all these birds are miniature " Moreporks." 



During the day the Spotted Nightjar may be found upon 

 the ground, or close to it, reposing in slumber, but with the 

 waning of the light and the oncoming of twilight its move- 

 ments while hawking for insects are particularly rapid and 

 stealthily silent. Judging by the scarcity of the bird in the 

 southern latitudes during the winter, I am of opinion that 



