Genus TICHODROMA. 
Certhia apud Linneus, Syst. Nat. i. p. 184 (1766). 
Tichodroma, Mlliger, Prodr. p. 210 (1811). 
Petrodroma apud Vieillot, Nouv. Dict. xxvi. p. 106 (1818). 
Tus genus, which contains only one species, whose range is given in the following article, is 
very Closely allied to Sitta and Certhia, and, indeed, differs from the latter chiefly in its bright 
coloration and in its habits; for it frequents rocks in elevated mountain-ranges, and avoids woods, 
where Certhia familiaris is usually to be found. As that species climbs about the trees, so the 
Wallcreeper climbs about the rocky portions of the mountains, descending to the valleys only 
during the cold portion of the year. It feeds on insects of various kinds, which it procures in 
the cracks and crannies of the rocks. 
Its nest, which is placed in a crack or hole in a rock, is bulky, and is constructed of moss 
and wool; and its eggs are white, very finely dotted with blackish at the larger end. 
Tichodroma muraria, the type of the present genus, has the bill slender, long, much wider 
than high at the base, narrowing to a point at the tip; nostrils elongated, placed in the anterior 
part of the long nasal depression; gape without any bristles; wings very long and broad, the 
first quill short, the second rather shorter than the seventh; tail moderately long, even or 
slightly rounded; legs strong, but rather slender than otherwise, the tarsus covered anteriorly 
with four indistinct plates and three inferior scutelle; toes rather long, claws strong, curved 
and pointed, the hind claw as long or longer than the toe. 
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