BIRDS. 



The praiseworthy endeavour, at present being made, to trace the migrations of our own 

 periodical visitors, we must admit to be a subject most difficult to follow, and, I feel sure, one 

 without any end or probibility of making much of, as most species of migratory birds are so 

 extensively distributed, and the impossibility of finding out in which direction the individuals of 

 a species travel, and the extent of country they fly over, and whether, when observed, they 

 are really migrating. 



There seems to be little doubt but that the time when different kinds of birds moult, has 

 frequently a good deal to do with their periodical migratory flights. The young birds of many 

 of the migratory species which take the most extensive flights in autumn, do not cast their flight 

 feathers till the following autumn an arrangement, probably, purposely to enable the species to be 

 always able to take long flights at almost any season ; the old birds, of such kinds, moulting their 

 flight feathers, either when they are engaged with their young and have not to travel far, or very 

 soon after the young have left them, and acquiring a perfect set of flight feathers previous to winter. 

 The young of such as do not breed the year after being hatched, probably moult gradually during 

 the following summer and autumn, so as to be able to fly well during the time they are moulting. 

 Some species of non-migratory birds, as the crows, the young of which also seem to retain 

 their first flight feathers till the following year; but the young starlings and larks cast their 

 flight feathers in early autumn, undergoing a complete moult as the old birds do. But why 

 the young birds of some non-migratory species have their flight feathers renewed in autumn, 

 and others closely allied have not, I cannot explain. The young thrushes, like the crows, I 



