I9I2. Patten. — Wre7is on Migration, 129 



of grain, etc., is one of the few exceptions, and even this 

 species moves about the country in considerable numbers. 



To return to the wing-power of the Wren, It is true its 

 flight feathers are short, but if so they are strongly built, 

 as is the whole wing, and we find the same holds good in the 

 case of many other short-winged birds, many which have 

 heavy body-weight to sustain, and yet are excellent fliers 

 when put to the test. It seems to me that what is most im- 

 portant of all, in considering the migratory flight in birds, is 

 their powers of endurance. Long pointed pinions are very 

 useful to sea-birds, endowing them with buoyancy enabling 

 them to slacken their speed as they survey the waters below 

 for food or to indulge in fantastic aerial gyrations. But 

 land-birds, whose food is not at hand and whose environ- 

 ment is totally foreign when crossing the sea, are not possessed 

 of, and can manage to dispense with, such wing-faculties. 

 What is required is the power of flying straight ahead at 

 their accustomed speed, backed by sufficient endurance of 

 wing power to enable them to keep up, and sufficient vitality 

 to enable them to live down the pangs of hunger, thirst, 

 and exposure to adverse weather. Surely the hardy, 

 ubiquitous Wren, a denizen even of the bleakest, almost 

 treeless and wind-swept areas of the country, where it is 

 as much at home as in sheltered woods and glades, must 

 be accredited with such endurance of flight ; and as for 

 speed, anyone who watches a Wren dart across an acre of 

 open field will be enabled to estimate for himself what rapid 

 progress could be made in a cross -channel migration by this 

 species. Structurally the Wren is a strongly framed bird 

 and its wing musculature is in no way inferior in develop- 

 ment to that of the smaller warblers of somewhat similar 

 body -weight ; its reproductive powers are notoriously great, 

 its voice is particularly strong, and altogether physiologi- 

 cally it seems to be a markedly hardy bird. 



An interesting feature in connection with the Tuskar 

 migration of Wrens which I witnessed, is that the two 

 birds obtained in autumn proved to be males, while the ten 

 taken in spring are females. I wish I had secured more in 

 the autumn to satisfy myself that there is a tendency for 

 the sexes to keep apart when on migration. The spring 



A 2 



