172 NATURAL HISTORY 



caverns ; and do, insect-like and bat-like, come forth at 

 mild times, and then retire again to their latebrce. Nor 

 make I the least doubt but that, if I lived at Newhaven, 

 Seaford, Brighthelmstone, or any of those towns near the 

 chalk-cliffs of the Sussex coast, by proper observations, I 

 should see swallows stirring at periods of the winter, when 

 the noons were soft and inviting, and the sun warm and 

 invigorating. And I am the more of this opinion from 

 what I have remarked during some of our late springs, that 

 though some swallows did make their appearance about the 

 usual time, viz., the 13th or 14th of April, yet, meeting 

 with a harsh reception, and blustering cold north-east 

 winds, they immediately withdrew, absconding for several 

 days, till the weather gave them better encouragement. 1 



LETTER XIII. 



TO THE HONOURABLE DAINES B ARLINGTON. 



April 12, 1772. 



[ HILE I was in Sussex last autumn, my resi- 

 dence was at the village near Lewes, from 

 whence I had formerly the pleasure of writing 

 to you. On the 1st of November, I remarked 

 that the old tortoise, formerly mentioned, 

 began first to dig the ground in order to the forming its 

 hybernaculum, which it had fixed on just beside a great 



1 Writers on this subject do not as a rule distinguish between tor- 

 pidity and hybernation. There are numerous instances of swallows 

 becoming torpid, but none of their hybernating, none of their being 

 aroused from a dormant state by unusually warm weather in early 

 spring, which latter fact, says Mr. Blyth, cannot be too much impressed 

 on those who still advocate the theory of the hybernation of a portion 

 oi these birds. It should be remembered also, he says, that the adults 

 01 one species, the chimney swallow, and the young of all, moult during 

 the winter months. ED. 



