2. Passeres diacromyodae.
C. Suboscines.
This group contains only the two Families Menuridae (Lyre-birds) and Atrichornithidae (Scrub-birds), each with one genus, Menura and Atrichornis respectively. The former possesses three pairs of vocal muscles, the latter only two pairs;[[278]] Menura, moreover, has a peculiarly long sternum, constricted towards the middle, while Atrichornis has but rudimentary clavicles, being thus unique among the Passerine forms.
Fam. I. Menuridae.–Lyre-birds have a stout bill; very long and powerful metatarsi, with robust elongated straight claws; and somewhat short rounded wings, with eleven primaries and ten secondaries. The tail has sixteen rectrices, and in the males of two species has the exterior pair of feathers curved like a lyre, with very narrow outer and very broad inner webs; the next six pairs have very distant barbs and no barbules, except towards the base; while the two median plumes have narrow inner and no outer webs, and after crossing below, curve boldly outwards. The tongue is sagittate, the furcula U-shaped, the after-shaft rudimentary; the adults have no down. M. superba of New South Wales and South Queensland, some thirty-three inches long, is dull brown, with a slaty tinge above, and more rufous throat, wings, and tail-coverts; while the outer rectrices exhibit regular notch-like transparent or blackish markings on the chestnut inner webs, caused by the absence of barbules. The naked orbits are bluish or lead-coloured. The female has a long, broad, normal tail, the median feathers exceeding the rest. M. victoriae, of Victoria, is darker, with more boldly marked outer rectrices. M. alberti, of Queensland, and the Richmond and Clarence River districts of New South Wales, is redder above, and has the tail less lyrate, the outer feathers being shorter, with no transparent notches.
Fig. 106.–Lyre-Bird. Menura superba. × ⅒.
Lyre-birds haunt precipitous sandy gullies in thick forests with tangled undergrowth, whether inland or near the coast; and, though able to fly, live chiefly upon the ground, whence they leap, when scared, to branches even ten feet high. They run with the tail horizontal, and scratch among fallen leaves for insects–especially coleoptera–myriapods, worms, and molluscs; the solitary individuals or pairs which are usually observed being particularly shy. Each cock has a walk or playground, and scrapes little hillocks or hollows for dancing places, where he struts or pirouettes with erect tail and drooping wings, scratching, pecking, and singing at intervals. Apparently, however, he is not polygamous. The normal cry is a loud, liquid, gurgling sound; but the Pheasants, as the Colonists term them, are clever mockers, imitating a cock's crow, a hen's cackle, a dog's bark or howl, the Laughing Jackass's note, or even the setting of a saw. The tail-feathers are said to be shed after breeding, and to be fully developed only by the fourth year, when males begin to sing. The oval, domed nests, placed on ledges of cliffs, on tops of old stumps, in forks of trees, or by fallen logs, are loose bulky masses of sticks, bark, grass, leaves, ferns, and moss, lined with roots and the bird's feathers. The one large egg has a stone-grey, brown, or dark purple ground-colour, blotched, dotted, and streaked with purplish or blackish-brown. The chicks are said to be covered with black down in M. victoriae, white in M. alberti, and brownish in M. superba; and to remain six weeks in the nest. The hen sits with her tail curled sideways or forwards. The flesh is dark, tough, and unpalatable.
Fam. II. Atrichornithidae.–Atrichornis has a large bill; moderate scutellated metatarsi; extremely short wings with eleven primaries, the outer of which is very small, and some eight secondaries; and a long, broad, graduated tail with twelve rectrices. The tongue is sagittate, the aftershaft rudimentary, and no down is present on adults. A. clamosa of Western Australia, about eight and a half inches in length, is brown above, barred with dusky, and reddish-white below, with a black pectoral patch; A. rufescens of New South Wales has the lower parts like the upper. The females appear to be unknown. These very shy birds haunt dense scrub, or grassy and bushy tracts, being very difficult of observation; they mimic the notes of other species cleverly, and also utter a peculiar noisy cry. They scratch in the ground, probably for insect-food.
D. Oscines.
Of this group, or the true singing birds, the anatomy is even less worked out than that of the Suboscines, and consequently the relationships are in many cases extremely doubtful. The Hirundinidae stand distinctly apart, with no other Families near them, though some similarity of habits, and possibly of structure, may be recognised in certain Muscicapidae (especially if Artamus be included among them), and to a less extent in a few Sturnidae; yet almost as much resemblance may be perceived in some Tyrannidae, which (not being Oscinine) can have no affinity to the Hirundinidae. The likeness is therefore probably one of analogy only, and, if so, of no taxonomic value. Here again it must be stated that the Oscines hardly attain more than the rank of a Family, and that in the Passeriformes the Families have not the same value as in the foregoing Orders.