56 
FALCONING. CIRCUS. 
slightly emarginate ; oesophagus very wide, with an extremely 
large crop ; proventriculus much dilated ; stomach very large, 
round, with its muscular coat very thin ; pylorus without 
valves ; intestine of moderate length and width ; coeca very 
small ; cloaca very large and globular. Nostrils large, ovato- 
oblong. Eyes large, the lachrymal ridge not projecting. 
Aperture of ear very large, elliptical, with a bare space 
extending from it to the base of the lower jaw. Feet long ; 
tarsus slender, compressed, anteriorly and posteriorly scutel- 
late ; toes rather small, slender, scutellate above, unless at 
the base, the third and fourth connected by a rather large 
basal web ; the first stouter but considerably shorter than 
the second ; claws long, moderately curved, slender, com- 
pressed, tapering to a fine point ; those of the first and 
second toes much larger. Plumage very soft and generally 
blended ; feathers oblong ; a distinct rutf of narrow curved 
feathers from behind the eyes to the throat ; wings long, 
broad, much rounded, the fourth and third quills longest, the 
first about equal to the seventh, the outer four with the 
inner web sinuously cut out. Tail long, nearly even, or 
rounded. 
There is considerable affinity in this genus to the owls, 
more especially in the ruff, large aperture of the ear, and 
downy plumage. The Harriers fiy low, often in circles, 
pounce upon small quadrupeds, birds, and reptiles, or some^ 
times pursue birds in open flight, and feed occasionally on 
insects and fishes. They nestle on the ground. The female 
generally differs from the male in colour. Three species 
occur in Britain. 
18 . Circus cyaneus. Bing-Tailed Harrier. 
The wings extending to about two inches from the tip of 
the tail ; the fourth quill longest, the third almost equal. 
Male with the plumage light bluish-grey, the outer primaries 
black toward the end, the tail-coverts white. Female umber- 
brown above, pale reddish-yellow longitudinally streaked with 
brown beneath, tail-coverts white. Young similar to the 
female, with the tints richer. 
Male, 18:^, 39^, 13, l^V^ 2/^, 1/^^, Female, 21, 46. 
This species feeds on small birds, and the young of larger, 
but occasionally on grouse and partridges, often on young 
