CIRCUS. 123 
Genus CIRCUS. 
The genus Circus was established by Lacépéde (Mém. Classe Sc. math.- 
phys. Inst. iii. p. 506) in the year 1801. Previous to that date the 
Harriers were included in the genus Falco of Linnzeus. Lacépéde did 
not indicate any type; but Bonaparte, who afterwards unnecessarily sub- 
divided the genus, retained the Marsh-Harrier in his restricted genus 
Circus, and this bird may therefore be considered the type. 
The Harriers are intermediate between the Buzzards and the Hawks, 
having the somewhat long wings and short tarsus of the former, and 
the long tail and slender tarsus of the latter, but agreeing with both 
in having the lower half of the tarsus scutellated both at the back and 
front. 
This genus is almost cosmopolitan, and contains about twenty species, 
of which four are European, three of these breeding more or less commonly 
in the British Islands. 
The food of the Harriers is composed of small mammals, birds, reptiles, 
fish, insects, and birds’ eggs. Their nests are built on the ground; and 
their eggs, from three to five in number, are bluish white, generally 
spotless, but in some cases marked with pale brown; when held up to the 
light the bluish-green colour which underlies the white ground-colour is 
always observable. 
