MIGRATION. 
377 
cannot be taken as proved, when we see our Swallows 
passing three or four, or perhaps more, foreign species on 
their road, while the latter remain in their homes both 
winter and summer. I do not say that this supposition 
solves the riddle which gives to us the Quail, Corncrake, 
Water Bail, and others, while at the same time we sud¬ 
denly see them appear before us in the primaeval forests 
of Central Africa, while I and others have found Quails 
wintering on the cold table-lands of Central Spain, in 
Italy, in Greece, in Egypt, and in Nubia, besides Water 
Rails and Crakes, which are to be found on nearly all 
the lakes of Lower Egypt. One thing our theory does 
prove, however, that it is not want of food which compels 
birds to leave us and fly hundreds of miles away. 
The stubble still bedecks our fields; the trees are yet 
green, and the cheery chorus of frogs still treats us to 
a sociable concert; the sun’s rays are yet warm, and 
the nights mild: but for all this the journey is begun. 
The Swift has reared her brood, and taught them to 
cater for themselves; the young are as active and lively 
as she is, and the whole party now prepare to start for 
foreign lands. On the 1st of August they leave us, and 
hasten to Central Africa, as though it was their veritable 
home,—oh, that they did not quit us before May ! Their 
journey is accomplished in an extraordinary short space 
of time : by the 5tli of August I have seen them arrive in 
Kartoum, 15° North latitude. They are singular crea¬ 
tures as regards their migrating. Ever punctual, they 
leave the whole of Spain at the same time as they 
forsake Germany; yet, curiously enough, they are 
still to be found on the Dovrefjeld, in Norway, their 
northernmost limit, as late as the end of August; 
and they may also be seen somewhat later with 
3 E 
