LITTLE RED-BILLED HAWK. 53 
genera, and gave their definitions; but he, ike Linneus, 
retained the generic name Falco for each species. I 
think he was right, and if this were the place for 
arguing the question, I could easily support this opinion 
by more logical proof. While admitting, therefore, a 
certain division into sub-genera, I shall follow the 
example and authority of Temminck, and adopt one 
uniform generic name for each of the several great 
families which I shall have to deal with in the progress 
of this work. 
I have deviated a little from the arrangement of 
M. Temminck, in placing the sub-genus Astur before 
that of Aguila. In this I have followed Schlegel, and 
I shall do the same with the only species I am called 
upon to describe of the sub-genus Circus. There are, 
I think, many sound reasons why these sub-genera 
should be close to each other. alco and Astur 
contain the most typical or perfect divisions of the 
family, while the Harriers form a good passage from 
_the Hawks to the Eagles. 
Falco Gabar is a native of both southern and wes- 
tern Africa, where it was discovered by Le Vaillant, 
the end of the last century. He says it was not uncom- 
mon; that it built in the fork of a high tree; and that 
its egg, like that of its congener the Goshawk, was 
white. We know nothing of its habits or propagation 
in Europe. 
An adult male in the Norwich Museum, has the 
head, nape, and back of a uniform greyish brown or 
dark slate-colour; chin, throat, and chest of a lighter 
grey; the belly, thighs, and under wing coverts white, 
with delicate, thin, transverse bars of grey. Primary 
quill feathers hair brown, barred above and below with 
a darker tint, the tips being conspicuously margined 
