The woodlark repairs to southern Europe during the winter, but a few also regularly push further southward, and cross again in spring. The pied wagtail and its northern variety, called after the late Mr. Yarrell, repair to southern Europe on the approach of winter, and many also cross the great inland sea and proceed a long way into Africa; we found the former very common up the Nile to the second cataract. The grey wagtail, although nowhere so common, follows the same course and pushes northward at the same time with its congener in spring. The yellow wagtails of Europe have been so frequently confounded and misnamed, that until the student has carefully examined specimens of each he will be almost sure to become confused. There is, first, the yellow wagtail of the British islands, called also Ray's wagtail, that migrates to the continent in winter, but we opine not to southern Europe; this bird has been mistaken for the yellow wagtail of the continent, first described by Linnaeus. Enormous flocks of the last-named bird cross regularly to and from Africa annually: probably not a straggler remains in either country after the migratory seasons are over. We have repeatedly noticed varieties of this wagtail with grey and black-colored heads, which many naturalists consider as specific differences, whilst others appear to class them under the head of a race or variety of the _Motacilla flava_ of Linnaeus. We are enabled so far to strengthen the latter opinion, by the fact that in a large series of skins collected from flocks of yellow wagtails during their migrations across the Mediterranean, we could make out a gradual transition from the one state of plumage to the other, and we frequently found the grey, black, and olive-headed (or yellow wagtail proper) all in one flock and constantly associating together, and with the same call-note; the only difference was the call-note in autumn in some was noticed to be harsher; these, however, we ascertained to be birds of the year. The rook is migratory in south-eastern Europe, and repairs to the delta of the Nile in large flocks; sometimes it is driven by stress of weather to the islands of the mid and western Mediterranean. {64} The northern portion of Africa is a favorite resort for the starling in winter, when flocks may be constantly seen all over the south of Europe; they quit, however, in spring and go northward. The jay has been recorded as migratory, and said to frequent north Africa, Malta, and Egypt. We cannot, however, find any authentic confirmation of this statement. All the European flycatchers cross the Mediterranean very punctually. The spotted bird is by far the most numerous, next the pied, and in a much less proportion, the white-necked flycatcher. The first has a very extensive geographical range, embracing the whole continent of Africa and Europe, and breeds in great numbers even in North Britain, where we have seen large flocks in autumn pursuing their retrograde coarse southward.