his reference to this being roughly in the same latitude but reached by a different "line of flight," suggests that it is an exception; this will be shown when some hundreds more cases have been collected. It may, however, be found that some birds deliberately launch forth in search of new homes, though at present it looks more like a bird which on approaching the breeding area had banded itself with the wrong local body of travellers.
A bird marked at Cassel in western Germany has been recorded from Barcelona in Spain; this so far single record may indicate that storks get lost, that there is no regular direction, or that there is more than one, a south-westerly as well as a south-easterly route. That too, we hope, will be shown in the future.
That much will be learnt from storks is evident, but the lessons will be only general; each migratory species must be treated separately, and to some extent this is being done. In the opening chapter I mentioned the uncertainty about the behaviour of any individual song thrush, merely as an example So far, the few records of marked song thrushes add to rather than solve this problem. Years ago the song thrush was looked upon as a permanent resident so far as Britain was concerned. Then it was found to be migratory even in Britain, and it was suggested that each song thrush performed a short
