PICUS. 353 
thologists cannot agree as to which species would have been regarded by 
Linnzus as typical. Of the eighteen species with which he was acquainted, 
seven belong to the black-and-white group. If we add to these the Black 
Woodpecker and its three allies, which seem to me to be generically 
inseparable, there can be no possible doubt that Linnzus must have 
considered this group of eleven species the typical one, the other eight 
species being obviously aberrant members of the family. In the absence 
of any rule to guide me, I accept P. major as the type, on the ground that 
it has been so regarded by the majority of ornithologists. 
The distinguishing characteristic of the Woodpeckers belonging to this 
genus is the coloration of their plumage, which in typical examples is pied 
black and white, with more or less scarlet or, in rare instances, yellow on 
the head of the male; but in some aberrant species the white disappears 
altogether, leaving the colours black and crimson. 
The limits of this genus have not yet been accurately determined, and 
it is impossible to say how many species it contains. It is principally 
confined to the Palearctic and Nearctic Regions, extending into the 
northern portions of the tropics. 
The birds in this genus frequent large woods, groves, parks, and orchards, 
where they climb about the trees, digging into the bark and decaying 
timber with their stout bills in search of food. Their flight is moderately 
quick and very undulatory, but seldom long sustained. Their notes are 
loud, harsh, and piercing. Their food is almost exclusively composed of 
insects and larve. They breed in holes of timber, which they generally 
excavate themselves, making no nest, and lay white and highly polished 
eggs. 
VOL. Il. 
