NATURAL HISTORY OF SELBO11NE. 53 



The vast rains ceased with us much about the same time as with 

 you, and since we have had delicate weather. Mr. Barker, who has 

 measured the rain for more than thirty years, says, in a late letter, that, 

 more has fallen this year than in any he ever attended to ; though 

 from July 1763 to January 1764, more fell than in any seven months 

 of this year. 



LETTEE XXJII. 



TO THE SAME. 



SELBORNE, Feb. 28th, 1760. 



DEAR SIR, It is not improbable that the Guernsey lizard and our 

 green lizards may be specifically the same ; all that I know is, that, 

 when some years ago many Guernsey lizards were turned loose in 

 Pembroke college garden, in the University of Oxford, they lived a 

 great while, and seemed to enjoy themselves very well, but never bred. 

 Whether this circumstance will prove anything either way I shall not 

 pretend to say. 



I return you thanks for your account of Cressi Hall ; but recollect, 

 not without regret, that in June 1746 I was visiting for a week together 

 at Spalding, without ever being told that such a curiosity was just 

 at hand. Pray send me word in your next what sort of tree it is that 

 contains such a quantity of herons' nests ; and whether the heronry 

 consists of a whole grove of wood, or only of a few trees. 



It gave me satisfaction to find we accorded so well about the 

 caprimulgus; all I contended for was to prove that it often chatters 

 sitting as well as flying ; and therefore the noise was voluntary, and 

 from organic impulse, and not from the resistance of the air against the 

 hollow of its mouth and throat. 



If ever I saw anything like actual migration, it was last Michaelmas 

 Day. I was travelling, and out early in the morning ; at first there 

 was a vast fog ; but, by the time that I was got seven or eight miles 

 from home towards the coast, the sun broke out into a delicate warm 

 day. We were then on a large heath or common, and I could discern, 

 as the mist began to break away, great numbers of swallows (hirundines 

 rusticce) clustering on the stunted shrubs and bushes, as if they had 

 roosted there all night. As soon as the air became clear and pleasant 

 they all were on the wing at once ; and, by a placid and easy flight, 

 proceeded on southward towards the sea ; after this I did not see any 

 more flocks, only now and then a straggler. 



I cannot agree with those persons that assert that the swallow kind 

 disappear some and some gradually, as they come, for the bulk of them 

 seem to withdraw at once ; only some stragglers stay behind a long 

 while, and do never, there is the greatest reason to believe, leave this 

 island. Swallows seem to lay themselves up, and to come forth in a 

 warm day, as bats do continually of a warm evening, after they have 

 disappeared for weeks. For a very respectable gentleman assured me 

 that, as he was walking with some friends under Merton Wall on a 

 remarkably hot noon, either in the last week in December or the first 



