78 THE NATURAL HISTOEY 



rare instance ! for they usually withdraw within the first 

 week.i 



On September the twenty-fourth three or four ring-ousels 

 appeared in my fields for the first time this season : how punctual 

 are tkese visitors in their autumnal and spring migrations ! 



LETTER XXXVIII. 



TO THE SAME. 



Selborne, March 15, 1773. 



Dear Sir, 



By my journal for last autumn it appears that the house-martins 

 bred very late, and staid very late in these parts ; for, on the 

 first of October, I saw young martins in their nests nearly fledged ; 

 and again, on the twenty-first of October, we had at the next 

 house a nest full of young martins just ready to fly ; and the old 

 ones were hawking for insects with great alertness. The next 

 morning the brood forsook their nest, and were flpng round the 

 village. From this day I never saw one of the swallow kind till 

 November the third ; when twenty, or perhaps thirty, house- 

 martins were playing all day long by the side of the hanging 

 wood, and over my fields. Did these small weak birds, some of 

 which were nestlings twelve days ago, shift their quarters at this 

 late season of the year to the other side of the northern tropic .'' 

 Or rather, is it not more probable that the next church, ruin, 

 chalk-cliff, steep covert, or perhaps sandbank, lake or pool (as a 

 more northern naturalist would say), may become their hybema- 

 culum, and afford them a ready and obvious retreat ? '^ 



We now begin to expect- our vernal migration of ring-ousels 

 every week. Persons worthy of credit assure me that ring-ousels 

 were seen at Christmas 1770 in the forest of Bere, on the southern 



' See letter lii. to Mr. Barrington. 



[It is not uncommon to find a solitary swift as late as the first week of 

 September.] 



' [White here assumes that the martins he saw on November 3 were the same 

 late broods that he had noted in October, and was thus led to guess that they had 

 gone into some " hibernaculum " in the meantime. But his assumption was pro- 

 bably incorrect ; the party seen in November 3 was no doubt composed of travellers 

 from some other quarter. Had his curiosity taken him on a journey along the 

 coast during the time of migration, he would have become aware of the gradual 

 method of travelling adopted by these birds, and so have dispensed with the theory 

 of the "hibernaculum ".] 



