OF SELBORNE $7 



LETTER XXIIl 

 TO THOMAS PENNANT, ESQUIRE 



Selborne, February 28, 1769. 



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 any thing 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 1 746 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 con- 

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



It gave me satisfaction to find that 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 hoUow 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 dis- 

 cern, as the mist began to break away, great numbers of 

 swallows {hirundines rusticae) 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 



