CORVIDA, 19 
Choughs. All species are resident within the limits of this work 
except the Rook and the Hooded Crow, which are winter visitors 
to the North and North-West. Their summer quarters are, how- 
ever, not far off and their migrations are only partial and local 
The members of the genera Corvus, or the true Crows, Pica, 
the Magpies, Nucifraga, the Nutcrackers, and Pyrrhocorax, the 
Choughs, are birds of wide distribution but the members of the 
other genera are nearly all restricted to small areas. 
The Corvide vary a good deal inter se in structure and habit. 
In one or two genera ‘the nostrils are not so completely hidden 
by bristles as in the typical Crow. The majority feed completely 
on the ground, others are strictly arboreal. They all agree in 
laying four or five spotted eggs except certain species of the 
genus Podoces, which lay white eges in burrows. The mode of 
nidification of the remaining genera varies greatly, some 
species breeding in holes of trees and cliffs, alae aflnene the 
majority, constructing large nests of sticks and twigs. Most of 
them are omnivorous, but some of the smaller tropical species 
appear to confine their diet to insects. 
The Corvide, as a family, have few characters in common, and 
yet there is no group of birds which is more easily recognized. 
Key to Genera. 
A. Nostrils distant from forehead about one- 
third length of bill; narial bristles rigid and 
straight, “reaching tu about middle of bill ; 
or Hee bristles and feathers of face need. 
@. Vail much shorter than wine............ Corvus, pv. 20. 
6. Tail much longer than wing ............ PICA, ps oi; 
B. Nostrils distant from forehead less than one- 
quarter length of bill; narial bristles or 
plumes short, never reaching to middle of 
bill. 
. Tail greatly graduated, outer feathers less 
than half lene th of taal! 
a’. Middle tail-feathers uniformly wide 
throughout or widening gradually to- 
Pas tip. 
. Bill red or yellow. 
a". Tail more than twice leneth of 
SNE Cae tes cnc or iete oS bois) a3 . Urocissa, p. 40. 
g'", Tail less than twice “Jeneth of 
CUNO regan ones e's Rete Cissa, p. 45. 
UNS STINE VEO er oe bam cleace Cee vg eee DENDROCITTA, p. 47. 
b’. Middle tail-feathers suddenly broadening 
TO WORM SHEN meee eet siatsies <al sic «5 CrYPSIRHINA, p. 56. 
d. Tail not much graduated, outer feathers 
more than half length of tail. 
ce’. Graduation of closed tail less than length 
of tarsus; rictal bristles extremely 
LONG ce casiccsteuetae S010 OES Ob Oe Oe PLATYSMURUTS, p. £ 
GZ 
or 
92) 
