i8 93 . THE BRITISH ASSOCIATION ADDRESSES. 299 



over the countries bordering on the Mediterranean; but, along with 

 it, in Andalusia alone is found another species, Cal. batica, of a rather 

 darker colour, and with the secondaries generally somewhat shorter. 

 Without further knowledge than that obtained from a comparison ot 

 skins, it might be put down as an accidental variety. But the field 

 naturalist soon recognises it as a most distinct species. It has a 

 different voice, a differently shaped nest ; and, while the common 

 species breeds in the plains, this one always resorts to the hills. The 

 Spanish shepherds on the spot recognise their distinctness, and have 

 a name for each species. Take, again, the eastern form of the 

 common song-thrush. The bird of North China, Turdus auritus, 

 closely resembles our familiar species, but is slightly larger, and there 

 is a minute difference in the wing formula. But the field naturalist 

 has ascertained that it lays eggs like those of the missel-thrush, and 

 it is the only species closely allied to our bird which does not lay eggs 

 of a blue ground colour. The hedge accentor of Japan [Accentor 

 rubidus) is distinguished from our most familiar friend, Accentor modular is, 

 by delicate differences of hue. But, though in gait and manner it 

 closely resembles it, I was surprised to find the Japanese bird 

 strikingly distinct in habits and life, being found only in forest and 

 brushwood several thousand feet above the sea. I met with it first 

 at Chinsenze — 6,000 ft. — before the snow had left the ground, and in 

 summer it goes higher still, but never descends to the cultivated land. 

 If both species are derived, as seems probable, from Accentor immacu- 

 latits of the Himalayas, then the contrast in habits is easily explained._ 

 The lofty mountain ranges of Japan have enabled the settlers there 

 to retain their original habits, for which our humbler elevations have 

 afforded no scope." 



Migration of Animals. 



In the long-studied subject of the migration of birds and other 

 animals, the field naturalist can also still find continuous and profit- 

 able occupation ; and Canon Tristram calls attention especially to an 

 exceptional phenomenon, " Not the mere wanderings of waifs and 

 strays, nor yet the uncertain travels of some species, as the crossbill 

 in search of food, but the colonising parties of many gregarious 

 species, which generally, so far as we know in our own hemisphere, 

 travel from east to west, or from south-east to north-west. Such are 

 the waxwing (Ampelis garrula), the pastor starling (Pastor roseus), and 

 Pallas's sandgrouse, after intervals sometimes of many years, 

 or sometimes for two or three years in succession. The wax- 

 wing will overspread Western Europe in winter for a short 

 time. It appears to be equally inconstant in its choice of 

 summer quarters, as was shown by J. Wolley in Lapland. The 

 rose pastor regularly winters in India, but never remains to breed. 

 For this purpose the whole race seems to collect and travel north- 

 west, but rarely, or after intervals of many years, returns to the same 



