_Description._--Above greyish white, transversely barred with blackish; wings black, with golden-yellow shafts, and white bars on the outer webs; rump white, with smaller black cross bars; crested head black; sides of head and whole neck in front yellow; malar stripe red; abdomen white, with regular transverse black bars; under wing-coverts yellowish white; bill and feet black: whole length 13·0 inches, wing 6·8, tail 4·9. _Female_ similar, but no red malar stripe.
The species commonly called _Carpintero_ in the Argentine country, and ranging south to Patagonia, is one of a group of the Picidæ of South America which diverge considerably in habits from the typical Woodpeckers. On trees they usually perch horizontally and crosswise, like ordinary birds, and only occasionally cling vertically to trunks of trees, using the tail as a support. They also seek their food more on the ground than on trees, in some cases not at all on trees, and they also breed oftener in holes in banks or cliffs than in the trunks of trees. As Darwin remarks in 'The Origin of Species,' in his chapter on Instinct, these birds have, to some slight extent, been modified structurally in accordance with their less arboreal habits, the beak being weaker, the rectrices less stiff, and the legs longer than in other Woodpeckers. In South Brazil and Bolivia the _Colaptes campestris_ represents this group, in Chili _C. pitius_, and in the Argentine country _C. agricola_.
Azara's description, under the heading _El Campestre_, probably refers to the Brazilian species, but agrees so well in every particular with the pampas Woodpecker that I cannot do better than to quote it in full.
"Though this name (_Campestre_) seems inappropriate for any Woodpecker, no other better describes the present species, since it never enters forests, nor climbs on trunks to seek for insects under the bark, but finds its aliment on the open plain, running with ease on the ground, for its legs are longer than in the others. There it forcibly strikes its beak into the matted turf, where worms or insects lie concealed, and when the ant-hills are moist it breaks into them to feed on the ants or their larvæ. It also perches on trees, large or small, on the trunks or branches, whether horizontal or upright, sometimes in a clinging position and sometimes crosswise in the manner common to birds. Its voice is powerful, and its cry uttered frequently both when flying and perching. It goes with its mate or family, and is the most common species in all these countries. It lays two to four eggs, with white and highly polished shells, and breeds in holes which it excavates in old walls of mud or of unbaked brick, also in the banks of streams; and the eggs are laid on the bare floor without any lining."