The period of the migratory flight in the autumn of any particular genus or species is most probably referable to two causes: the first one of temperature, affecting the time of nesting; the second is the period at which the young arrive at maturity, or rather that period when they throw off paternal control or are thrown off themselves. When able to act independently and procure food on their own account, they flock together and migrate in a body. We know that, with rare exceptions, the young of the year migrate some weeks in advance of the parent birds; thus we can readily conceive the whole of the large raptorial birds nesting about the same time over widely extending districts in Northern Europe; when the many young arrive at a self-dependent stage there would be a simultaneous movement, ending in a universal migratory rush. This period of self-dependence is arrived at much more quickly in some birds than in others, for species like the Knot, Grey Plover, Godwit, and Sanderling, nesting in very high latitudes, leave our shores the last in the spring of any of the migrants, and their young are amongst the first to return in autumn. The order of migration, more especially in connection with the shore birds, is the occurrence very early in autumn--July or August--of a few _old_ birds in summer plumage, either barren or such perhaps as have been prevented nesting, then the young in large flocks, and some weeks subsequently old birds. The season of 1881-82 will long be remembered by east coast ornithologists for the number of rare visitants which have appeared from time to time, driven to westward of their ordinary migration lines by the prevailing winds from N. and N.E. to E. and S.E., generally strong and frequently increasing to a severe gale. The fact of ten Ospreys having been seen or procured has already been mentioned; there were two occurrences of Tengmalm's Owl; the Rustic Bunting at Spurn; Lapp Bunting at Tetney, on Lincolnshire coast; White-spotted Blue-throat at Cley, in Norfolk; Glossy Ibis, five occurrences; Sabine's Gull, two on Norfolk coast; Kentish Plover, Lincolnshire; Blue-winged Teal, Teesmouth; and numerous other occurrences of scarcely secondary interest. These, as well as the rarer occurrences in Heligoland, have been separately treated in the notes on each species observed. WEST COAST OF SCOTLAND. Schedules, &c., were sent to thirty-eight stations, the same number as in 1880. We have received filled-in schedules from twenty-six stations, being same as last year. Generally the returns are light, and the scarcity of birds is accounted for by the reporters, and borne out by comparison of statistics, by the prevalence of westerly gales and winds (see General Remarks). The schedules show the same careful work as in former years.