1 64 A HISTORY OF BIRDS 



" occasionally," says Mr. Hudson, " in response to a note of 

 invitation, they all in a moment leave off feeding and fly to 

 one spot, and, forming a close cluster, and emitting a short, 

 excited, rapidly repeated note, display their wings, like beautiful 

 flags grouped loosely together ; some hold the wings up ver- 

 tically and motionless ; others half open and vibrating rapidly, 

 while still others wave them up and down with a slow, 

 measured motion." 



Such, then, are a few of the more striking cases of dances 

 among birds. But there remains yet to be described another 

 form of play connected with the period of sexual activity which 

 must be briefly referred to here. This concerns the remark- 

 able performances of the " Bower-birds" of Australia, of which 

 there are several species, all displaying similar habits ; con- 

 sequently space can be found here only for a single detailed 

 illustration. This shall be furnished by the " Gardener Bower- 

 bird" {Amblyornis inomatus). This species builds at the foot 

 of a small tree a kind of hut or cabin, some two feet in height, 

 roofed with orchid stems that slope to the ground, regularly 

 radiating from the central support, which is covered with a 

 conical mass of moss sheltering a gallery round it. One side 

 of this hut is left open, and in front of it is arranged a bed 

 of verdant moss, bedecked with blossoms and berries of the 

 brightest colour. As the ornaments wither they are removed 

 to a heap behind the hut, and replaced by others that are fresh. 

 The hut is circular and some three feet in diameter, and the 

 mossy lawn in front of it is nearly twice that expanse. Each 

 hut and garden are believed to be the work of a single pair of 

 birds. The use of the hut, it appears, is solely to serve the 

 purpose of a playing-ground, or as a place wherein to pay court 

 to the female, since it, like the bowers built by its near relatives, 

 are built long before the nest is begun, this, by the way, being 

 placed in a tree. 



The less elaborate "bower" of the Satin-bower bird 

 {Ptilonorhynchus holoserims) indicates an earlier stage in the 

 evolution of this remarkable custom. Herein a long gallery 

 or avenue is constructed of fine twigs placed on end, and roof- 

 less. The entrance to this is decorated with snail shells, 

 bleached bones and bright feathers. When complete the male 

 uses the bower, as we have indicated, as a courting-ground. In 



