538 CORVUS FRUGILEGUS. 



Female. — The female is precisely similar to the male, being 

 merely a little smaller. 



Length to end of tail 18^ inches; extent of wings 36 ; wing 

 from flexure 1 2 ; tail 7i ; bill along the back 2, along the edge 

 of lower mandible 2j^^ ; tarsus 2 ; first toe ^§, its claw {^ ; 

 second toe lOi twelfths, its claw j'^^ ; third toe l^^j, its claw 

 j% ; fourth toe ^^, its claw 6i twelfths. 



Variations. — Individuals of either sex vary considerably in 

 size. There is also a remarkable diversity in the form of the 

 bill, which has a ruder aspect and rougher surface than in the 

 other species, and not unusually has the point of the upper 

 mandible a little deflected to one side. The base of the low^er 

 mandible is generally dilated, in some cases in a very remark- 

 able degree, which is doubtless owing to the habit which the 

 bird has of cramming its sublingual pouch with food for its 

 young. Albino individuals sometimes occur, either pure white, 

 or more frequently yellowish- white or cream-coloured, with the 

 bill and feet also w^hite, and the eyes reddish. Patches of 

 Avhite are also sometimes seen on individuals. 



The plumage towards the period of the moult becomes ragged 

 and as it were tarnished with brown. The feathers of an indi- 

 vidual in a state of change shew a great difference, the old 

 ones being dull brown, the new beautifully glossed with green 

 and blue. The same circumstance is observable in the other 

 species. 



Habits. — The habits of the Rook form an interesting subject 

 of observation, and have been minutely described by various 

 wa-iters, some of whom, not content w^ith the phenomena pre- 

 sented by nature, have embellished their histories w^ith many 

 marvels supplied by their own active imagination. If we 

 w^alk abroad in the summer mornings, in a place not remote 

 from the haunts of this bird, Ave find it to be among the 

 earliest astir of those that betake themselves to the open 

 fields. While the dew is yet on the grass, even sometimes 

 in the early dawn, before the sun has emerged from beneath 

 the horizon, it urges its silent flight to some grassy field or hill, 



