40 BIEDS. 



■with difficulty, and we must leave to time the discovery of this mystery of 

 mysteries. 



Exceptional migration occurs when from some cause or other the ordinary 

 practice is broken through. One of the most extraordinary events known to 

 ornithologists is the irruption into Europe, in 1863, of Pallas's Sand-Grouse 

 {S. paradoxus). Of this bird, hitherto known only as an inhabitant of the 

 Tartar steppes, a single specimen was obtained at Sarepta, on the "Volga, in 1848. 

 In May, 1859, a pair were killed in Vilna, on the western borders of Russia; 

 and a few weeks later five examples were procured — one in Jutland, one in 

 Holland, two in England, and one in Wales. In 1860 another was obtained at 

 Sarepta; but in May and June, 1863, a flock of at least 700 spread over Europe, 

 reaching Sweden, the Faeroes, and Iceland in the N.W., and in the S. extending 

 to Sicily, and almost to the frontiers of Spain. On the sand-hills of Jutland and 

 Holland some of- these birds bred. In 1872 another visitation to Great Britain 

 was reported. 



Nocturnal concourse of migrants. Towards the close of summer, in dark, 

 cloudy, and still weather, a vast and heterogeneous concourse of birds may be 

 heard hovering over our large towns. It is supposed that these noises proceed 

 from migrating birds which have lost their way. Lord Lilford records that once 

 at Corfu he was startled by an uproar like a conflict overhead {Enc. Brit.). 



SONG. 



The deep booming of the Emeu, the harsh cry of the Guillemot, the wail of 

 the Plover, the whistle of the Widgeon, " the Cock's shrill clarion," the bleating 

 of the Snipe, or the drumming of the Ruffed Grouse, etc., are sounds made by 

 birds under the influence of love, etc., which may be regarded as a " song." 



Gestures akin to song. Akin to the " song " of birds are the peculiar gestures 

 which males perform during pairing. The Ruff dances on his hillock ; the 

 Snipe and some allies mount aloft and execute wild evolutions in the clouds ; 

 the Woodcock and many of the Goatsuckers beat the same aerial path evening 

 after evening with sudden and sharp turns ; the Capercailzie and Blackcock on a, 

 height throw themselves into curious postures. Other species of Grouse assume 

 strange attitudes, and run in circles tiU the turf is worn bare. The Peacock 

 spreads his train. 



NIDIFICATION. 



The making of a nest is a labour that is scamped, if not shirked, by many 

 birds. Some of the Auk tribe place their single egg on a bare ledge of rock, 

 where its peculiar conical shape is but a precarious safeguard against wind or 

 accident. Stone Curlew and Goatsuckers deposit their eggs without preparation 

 of the soil, but select carefully the spot for their procreant cradle. The Apteryx: 

 seems to trust its abnormally big egg to an excavation among the roots of a tree 

 fern. Female Ostriches scrape holes in the desert sand and promiscuously drop 

 their eggs, cover them, and leave incubation to the male, who discharges the duty 

 by night only and trusts by day to the sun's rays to keep up the warmth.. 



