Page:The Zoologist, 4th series, vol 6 (1902).djvu/292

242 human standpoint, they would be better calculated to inspire a feeling of scorn than of admiration in the minds of their mates; though in some cases, where brilliant colouring is thereby exposed to the feminine eye, admiration might modify the contemptuous feeling.

Among the Thrushes, the cock birds usually approach the hens with outstretched neck, drooping wings, and tail jerked upright. After pairing the cock bird stands straight up, with tail depressed, neck stretched, and bill in a line with the neck, and utters a screaming whistle. I have noticed this in the case both of the American Blue-bird (Sialia sialis) and the common Blackbird, the latter being a wild bird, which used to approach its hen upon the roof of my outdoor aviary, which runs parallel to the side of my conservatory.

The dances and postures of the Satin Bower-bird (Ptilorhynchus violaceus) are always accompanied by a continuous song, like water escaping down a sink or gully; even the checks, occasioned by bits of leaf or stick in the water, are admirably rendered. At intervals, when the bird takes a lateral hop, or changes its position, the gurgling and sizzling notes are interrupted by hoarse screaming whistles. The postures are a good deal varied; a common type is represented by the neck being somewhat retracted, the feathers of the nape and back raised, the tail span-roofed, drooped, the wings lifted alternately, whilst the bird sways from side to side. In another dance the head is stretched forward, the body held high, with all the feathers tightly appressed, but the tail still drooping. A third position is represented by the bird gazing fixedly at its mate, with the bill nearly touching the earth; the bird often carries a feather, dead leaf, or piece of food in its mouth when going through its performance, and its changes of form and posture are quick and startling.

One thing has astonished me somewhat with regard to this species: I find that both sexes, at different times, indulge in the same performances, both in dancing and singing, and whichever sex happens to be going through its evolutions is a source of terror to the other. As both my birds acquired their very dissimilar adult colouring in September, 1900, there can be no question as to their being genuine male and female.