BRITAIN'S BIRDS AND THEIR NESTS. 121 



ORDER, PTEROCLETES (SAND-GROUSE) ; 



Family, PTEROCLID^ (Only Family). 



PALLAS'S SAND=GROUSE 



(5yrrhaptes paradoxus). 



This bird is an inhabitant of the steppes of Central 

 Asia ; but at intervals extraordinary emigrations have 

 occurred, perhaps as a result of overcrowding of the 

 bird's proper area, in the same manner and with similar 

 result as in the case of certain mammals, such as the 

 Lemming of northern Europe. These overflows have 

 made themselves apparent to us as periodical irruptions 

 of great numbers of Sand-Grouse over the greater part of 

 Europe, even as far as our own islands. 



After some of these irruptions new colonies have been 

 established beyond the former Asiatic range ; but, as far as 

 northern Europe has been concerned, the w^anderers greatly 

 overshot their mark, and soon perished or were driven 

 away by the humidity of the climate and by human 

 persecution. During one of the greater irruptions, how- 

 ever, the species gained a nominal right to a place on 

 the British-breeding list. Invasions took place in 1859, 

 1863, 1872, and 1876, that in the second-named year 

 being an important one of considerable magnitude. In 

 1888 a great irruption occurred, and thousands of birds 

 reached this country. Clutches of eggs were taken in 

 Yorkshire and elsewhere ; and on the Culbin Sands, in 

 Moray, a nestling was discovered, and a second in the 

 following year. In 1908 a small invasion reaching our 

 islands occurred, and birds were also recorded in 1909. 

 The status of Pallas's Sand-Grouse on our list is abso- 



P 



