FLIGHT OF BIRDS. 221 



vernal and the autumnal crocus, which have such an affinity, 

 that the best botanists only make them varieties of the same 

 genus, of which there is only one species, not being able to 

 discern any difference in the corolla, or in the internal struc- 

 ture. Yet the vernal crocus expands its flowers by the 

 beginning of March at farthest, and often in very rigorous 

 weather ; and cannot be retarded but by some violence offered , 

 while the autumnal (the saffron) defies the influence of the 

 spring and summer, and will not blow till most plants begin 

 to fade and run to seed. This circumstance is one of the 

 wonders of the creation, little noticed because a common 

 occurrence ; yet ought not to be overlooked on account of its 

 being familiar, since it would be as difficult to be explained as 

 the most stupendous phenomenon in nature. 



Say, what impels, amidst surrounding snow 

 Congeal'd, the crocus' flamy bud to glow ? 

 Say, what retards, amidst the summer's blaze, 

 Th' autumnal bulb, till pale, declining days ? 

 The GOD OF SEASONS, whose pervading power 

 Controls the sun, or sheds the fleecy shower : 

 He bids each flower his quickening word obey, 

 Or to each lingering bloom enjoins delay. 



LETTER LXXXIV. 



TO THE HON. DAINES BARRINGTON. 



SELBORNE, August 7, 1778. 



Omnibus animalibus reliquis certus et uniusmodi, et in suo cuique 

 genere incessus est ; aves solse vario meatu feruntur, et in terra, et in 

 aere. PUN. Hist. Nat. lib. x. cap. 38. 



DEAR SIR, A good ornithologist should be able to distin- 

 guish birds by their air as well as their colours and shape, on 

 the ground as well as on the wing, and in the bush as well as 

 in the hand. For, though it must not be said that every 

 species of birds has a manner peculiar to itself, yet there is 

 somewhat in most genera at least that at first sight discriminates 

 them, and enables a judicious observer to pronounce upon 

 them with some certainty. Put a bird in motion, 



Et vera incessu patuit. 



Thus kites and buzzards sail round in circles, with wings 

 expanded and motionless ; and it is from their gliding manner 

 that the former are still called, in the north of England, 

 gleads, from the Saxon verb glidan, to glide. The kestrel, or 



