538 PALLAS'S SANDGROUSE 



1890. A few were recorded from various parts of the east of England (Norfolk, 



Lincolnshire, Yorkshire). 



1891. Recorded from Yorkshire, and the Moray area in Scotland. 

 1899. Reported from Lincolnshire and Yorkshire. 



1904. Reported from Yorkshire. 



1906. Recorded from Norfolk, Yorkshire, and East Lothian. 



1907. One reported from Middlesex. 



1908. A slight invasion was noticed in this year over a considerable part of 



Europe, including England (Kent, Essex, Hertfordshire, Yorkshire, 

 Cheshire, etc.). 



1909. Reported from Yorkshire. 



(Cf. Newton, Ibis, 1894, p. 186 ; Ussher and Warren, B. of Ireland, 1900, pp. 227- 

 229 ; Witherby and Ticehurst, British Birds, ii. pp. 126, 127 ; Gatke, Vogel- 

 warte Helgoland, Eng. trans., 1899, pp. 438-442 ; von Tschusi zu Schmidhoffen, 

 MittheiL Nat. Ver. Steiermark, 1889, Der Zug des Steppenhuhnes nach dem Westen, 

 1908 (1909); Jourdain, British Birds, iii. pp. 344-346; Macpherson, Visitation of 

 Pallas's Sandgrouse to Scotland in 1888 ; W. Evans, Proceedings of the Royal 

 Physical Society, Edinburgh, x., pt. i., 1889, pp. 106-126; Southwell, Birds of 

 Norfolk, iii. pp. 392-396 (cf. i. p. 376), and Zoologist, 1888, pp. 442-456 ; Bolam, 

 Berwickshire Naturalists Club Transactions, 1889, pp. 1-24 ; and others). 



Of the habits of the sandgrouse as a traveller it is unnecessary to say more than 

 is sufficient to emphasise the erratic nature of the movements. Of the 1863 irruption 

 as observed on Heligoland it was remarked that " small bands of three or five, 

 but also larger ones of twenty and even fifty individuals, were seen almost daily, 

 and sometimes, though in rarer instances, flocks of a hundred or more. These 

 latter for the most part were observed hastening along at a tremendous speed, 

 the flights, however, not proceeding in one direction, after the manner of a fixed 

 migratory movement, but irregularly in all directions, according to what appeared 

 to be the prevailing mood of a particular company " (Gatke, loc. cit.). This erratic 

 nature of the movement, coupled with the irregularity of the occurrence of such 

 movements, and with the absence of any definite return movement, separates these 

 phenomena from those of true migration. The movements are probably to be 

 regarded rather as sudden attempts at extension of range, due to obscure causes 

 the nature of which need not be discussed here. In support of this explana- 

 tion we have the evidence of the successful establishment of a new colony after 



