172 
NATURAL HISTORY 
caverns ; and do, insect-like and bat-like, come forth at 
mild times, and then retire again to their latebrce. IN'or 
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/ 
LETTER XIII. 
TO THE HONOUKABLE DAINES BAERINGTON. 
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 !N"ovember, 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 
^ 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 
troused 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 
oi one species, the chimney swallow, and the young of all, moult during 
the winter months. — Ed. 
