half of March, and in Central Europe not until the last half of March. It is perfectly certain that the Natal Swallows, if they only leave during the first half of April, even allowing only a few days in which to accomplish a journey of five thousand to six thousand miles, must go to some part of North Europe or to North-west Asia, since the Swallows which breed further south have arrived at their breeding-grounds before the South African birds have left their winter quarters. So far as it goes, this evidence is conclusive that, in case of the European Swallow, the individuals which go further north to breed go further south in winter.
It has been asserted that some European Swallows remain in South Africa through the greater part of the year, and Andersson even asserts that in some uncivilized parts they affix their nests to some projection of a rock or trunk of a tree. More evidence, however, on this point is required.
Between August and April there can generally be seen about Cape Town and the suburbs large numbers of Black Swifts, flying often at a considerable height above the ground, as is their usual habit. Mr. Layard believed these to be the European Swift, which spends the summer months in Europe, and disappears southwards in August or September. A careful comparison, however, of the European and South African bird seems to show that there are differences between them, the African bird being somewhat larger and darker in colour. Hitherto no authenticated observation on the breeding of the Black Swift in South Africa has been made; but if, as is now supposed to be the case, the South African bird is distinct, it probably does nest somewhere in South Africa, and at any rate the birds from about Cape Town do disappear during the winter months. We do not know where they go to.
Besides the migrants from Europe who come to South Africa to avoid the northern winter, there are a good many birds whose breeding range is in South Africa, and who migrate northwards during the South African winter, probably to Central Africa; about the exact migration range of these birds much less is known than about the movements of the European birds.
Among the more familiar or better known cases are those of the White-throated Swallow, which remains only from August to March; the Pearl-breasted Swallow; the large Stripe-breasted Swallow, one of the most familiar of the group, which generally builds its nest—a retort-shaped chamber entirely constructed of mud pellets—over a porch under the shelter of a verandah. Among other groups are the Carmine-breasted Bee-Eater, only found in north of the Vaal River, and the solitary Cuckoo, commonly known as the "Piet Mijn Vrouw."
All these birds are found in South Africa during the South African
