180 NATURAL HISTORY OF SELBORNE. 
narrow crevice ; and where they cannot pass on their bellies they 
will turn up edgewise. 
The particular formation of the foot discriminates the swift from 
all the British hirundines, and indeed from all other known birds, 
the hirundo melba, or great white-bellied swift of Gibraltar, ex- 
cepted ; for it is so disposed as to carry “omnes guatuor digitos 
anticos”—all its four toes forward; besides, the least toe, which 
should be the back toe, consists of one bone alone, and the other 
three only of two apiece—a construction most rare and peculiar, 
but nicely adapted to the purposes in which their feet are employed. 
This, and some peculiarities attending the nostrils and under man- 
dible, have induced a discerning* naturalist to suppose that this 
species might constitute a genus fer se. 
In London a party of swifts frequents the Tower, playing and 
feeding over the river just below the bridge ; others haunt some of 
the churches of the Borough, next the fields, but do not venture, 
like the house-martin, into the close crowded part of the town. 
The Swedes have bestowed a very pertinent name on this swal- 
low, calling it “ ring swala,” from the perpetual rings or circles that 
it takes round the scene of its nidification. 
Swifts feed on coleoptera, or small beetles with hard cases over 
their wings, as well as on the softer insects ; but it does not appear 
how they can procure gravel to grind their food, as swallows do, 
since they never settle on the ground. Young ones, overrun with 
hippobosce, are sometimes found, under their nests, fallen to the 
ground, the number of vermin rendering their abode insupportable 
any longer. They frequent in this village several abject cottages ; 
yet a succession still haunts the same unlikely roofs—a good proof 
this that the same birds return to the same spots. As they must 
stoop very low to get up under these humble eaves, cats lie in wait, 
and sometimes catch them on the wing. 
On the 5th of July, 1775, I again untiled part of a roof over the 
nest of a swift. The dam sat in the nest; but so strongly was she 
affected by a natural oropyy for her brood, which she supposed to 
be in danger, that, regardless of her own safety, she would not stir, 
but lay sullenly by them, permitting herself to be taken in hand. 
The squab young we brought down and placed on the grass-plot, 
where they tumbled about, and were as helpless as a new-born child. 
While we contemplated their naked bodies, their unwieldy dispropor- 
* John Antony Scopoli, of Carniola, M.D. 
