NATURAL HISTORY OF SELBORNE. gl 
PePre rR cose 
TO THE SAME. 
SELBORNE, WVov. 26th, 1770. 
DEAR SIR,—I was much pleased to see, among the collection of 
birds from Gibraltar, some of those short-winged English summer- 
birds of passage, concerning whose departure we have made so 
much inquiry. Now if these birds are found in Andalusia to 
migrate to and from Barbary, it may easily be supposed that those 
that come to us may migrate back to the continent, and spend their 
winters in some of the warmer parts of Europe. This is certain, 
that many soft-billed birds that come to Gibraltar appear there only 
in spring and autumn, seeming to advance in pairs towards the 
northward, for the sake of breeding during the summer months ; and 
retiring in parties and broods towards the south at the decline of the 
year : so that the rock of Gibraltar is the great rendezvous, and 
place of observation, from whence they take their departure each 
way towards Europe or Africa. It is therefore no mean discovery, 
I think, to find that our small short-winged summer birds of passage 
are to be seen spring and autumn on the very skirts of Europe; i: 
is a presumptive proof of their emigrations. 
Scopoli seems to me to have found the Azvrundo melba, the great 
Gibraltar swift, in Tirol, without knowing it. For what is his 
hirundo alpina but the afore-mentioned bird in other words? Says 
he “‘Omuia prioris” (meaning the swift); ‘sed pectus album, 
paulo major priore.” 1 donot suppose this to be anew species. It 
is true also of the szelba, that ‘‘ nzdificat in excelsis Alpium rupibus,” 
Vid. Annum Primum.™* 
My Sussex friend, a man of observation and good sense, but no 
* “ Annus I.” p. 166. Quite right, it is the cyfselus melba, Gmelin. The alpine or 
white-bellied swift of British authors, and communicated to Linnzus by John White 
during his residence at Gibraltar. There are a few instances recorded of its having been 
killed in Great Britain and Ireland. 
The letters from his brother while at Gibraltar would be exceedingly interesting to 
White while his attention was turned to migration, and there is little doubt that the great 
bulk of our migratory species follow the line as suggested in the text ; at the same time, 
however, some of the species, the common swallow for instance, has a very extensive 
range, and I believe is permanently resident nowhere. The more distant cannot be ex- 
pected to reach northern Europe or Great Britain, which in all probability are supplied from 
North or North-Eastern Africa. 
