The GROUND WOODPECKERS (Geositta) are birds with slender bodies, long, pointed wings, and short incised tails; the slightly curved beak is triangular at its base, and nearly equals the head in length; the legs are of medium height, the outer toes short, and the claws small.
THE BURROWING GROUND WOODPECKER.
The BURROWING GROUND WOODPECKER (Geositta cunicularia) is of a deep brown on the upper portions of the body and wings; the under side is pale brown, the throat whitish, breast spotted and striped with black, and the belly rust-red. The region of the eye is pale red, the shoulder-feathers have light edges, and the exterior quills are bordered and tipped with blackish brown, and shaded with red upon the inner web. The eye is brown, the beak whitish at its base and black towards its tip; the feet are blackish brown. According to Kittlitz these birds inhabit the barren plains of Chili and Patagonia, and are met with on the Bolivian Cordilleras to a height of from 3,500 to 4,500 feet above the level of the sea. We learn from the same authority that in its general habits the Geositta cunicularia closely resembles the Common Lark.
"The Casaeita, as this bird is called by the natives," says Darwin, "builds its nest at the bottom of a narrow cylindrical hole, which is said to extend horizontally to nearly six feet under ground, in any low bank of sandy soil by the side of a wood or stream. Here, at Bahia Blanca, the walls of those I have seen are built of hardened mud. I noticed that a bank that enclosed the courtyard of the house where I lodged was penetrated by round holes in a score of places. On asking the owner the cause of this, he explained that they were made by the Casaeitas, several of which I afterwards saw at work. It is strange that though the birds were constantly flitting over the low wall they were evidently incapable of forming an idea as to its thickness, otherwise they would not have made so many vain attempts. I do not doubt that each bird as it came to daylight on the opposite side was greatly surprised at the marvellous fact."
Gray tells us that this species is extremely tame, and almost constantly in motion. The stomachs of such as he examined contained the remains of beetles; whilst Kittlitz mentions having only found seeds and small stones. At certain seasons the call is a shrill, tremulous note.
The STAIR-BEAKS (Xenops) are a group of Brazilian birds, possessing a very peculiar formation of beak, the lower mandible being graduated upwards, whilst the upper portion of the bill is quite straight. The tail is formed of soft, rounded feathers, and the feet are powerful. We learn from the Prince von Wied that the members of this group associate in pairs, or small parties, and lead a very quiet, retired life within their native forests. Their food consists principally of insects, and whilst in search of these they tap upon the bark of the tree after the manner of the Woodpecker. According to our own experience they will also eat some kinds of nuts. The nest is usually placed in a hole in a tree. The various species, as far as we have ascertained, have nothing striking or peculiar in their cry.
THE HAIRY-CHEEKED STAIR-BEAK.
The HAIRY-CHEEKED STAIR-BEAK (Xenops genibarbis), an inhabitant of the Brazilian forests, is olive-brown on the upper parts of the body, greyish brown beneath, and white on the breast; a yellowish white line passes over the eyes, and there is a white patch behind the ear; the wings are striped with two shades of brown; the centre tail-feathers are reddish brown, the rest become deeper in shade towards the exterior; the outermost are almost black, spotted with rust-red. The length of this species is about four inches; the wing measures two inches, and the tail one inch and a half.
