Il8 NATURAL HISTORY. 



starlings, as it were, swim along; while missel-thrushes 

 use a wild and desultory flight ; swallows sweep over the 

 surface of the ground and water, and distinguish them- 

 selves by rapid turns and quick evolutions ; swifts dash 

 round in circles ; and the bank-martin moves with frequent 

 vacillations like a butterfly. Most of the small birds 

 fly by jerks, rising and falling as they advance. Most 

 small birds hop ; but wagtails and larks walk, moving 

 their legs alternately. Skylarks rise and fall perpen- 

 dicularly as they sing; woodlarks hang poised in the 

 air; and titlarks rise and fall in large curves, singing in 

 their descent. The whitethroat uses odd jerks and 

 gesticulations over the tops of hedges and bushes. All 

 the duck-kind waddle ; divers and auks walk as if fettered, 

 and stand erect on their tails ; these are the compedes of 

 Linnaeus. Geese and cranes, and most wild-fowls, move 

 in figured flights, often changing their position. The 

 secondary remiges* of Tringae, wild-ducks, and some 

 others, are very long, and give their wings, when in motion, 

 a hooked appearance. Dabchicks, moor-hens, and coots 

 fly erect, with their legs hanging down, and hardly make 

 any despatch ; the reason is plain, their wings are placed 

 too far forward out of the true centre of gravity ; as the 

 legs of auks and divers are situated too far backward.' 



Among the innumerable subjects which Gilbert White 

 investigated, there seem to have been few that interested 

 him more than the problem of the disappearance of the 

 swallows at the approach of winter. On this point he 

 never could make up his mind to fully accept the ordinary 

 theory of the migration of these birds in autumn to some 



* Wing-feathers. 



