It would almost appear that the great rush of migrants in September on the Bell Rock, and more noticeably on Isle of May, would also account for the collection of birds at stations on the west coast south of the Firth of Clyde, as the dates tally with each other on both coasts, to see which it is only necessary to compare between them under several of the species. I have also independent reports upon the large crowds of birds seen passing south over the Solway Firth at these dates, few of which appear to have been seen north of the Firth of Clyde.[6] Rushes have not been so large, yet they are indicated with tolerable precision by the returns. The extremely regular and open winter has no doubt much to do with this, the temperature in Great Britain having been higher than for many years previous. But these throbs or rushes being distinctly traceable is owing, on the other hand, I believe, to the prevailing wind fully as much as to the severity or non-severity of the weather. Rushes are normal phenomena in the West of Europe, because westerly or north-westerly or southwesterly winds usually prevail there. Regular or more dispersed movements of birds in the West of Europe are abnormal, because easterly winds are abnormal there. In 1880 we had a _spread-fan_ of migration, if I may so express it. In 1879 and 1881, in Scotland, we had a _closed-fan_ of migration. The natural result of the wide-spread fan is continuous streams of migration and no rushes; that of the closed-fan great throbs and rushes, for birds prefer to travel with a beam wind and wait for favourable winds, and do not often voluntarily start on their flight with a following wind. The occurrence of the white-spotted form of Blue-throated Warbler after a succession of tremendous S.E. gales, culminating in the dreadful hurricane of Oct. 14th, clearly shows, I think, that acts of voluntary migration do not take place in following winds. This Bluethroat was caught up and borne away, _nolens volens_, and our Mid-Atlantic notes in 1880 show similar abnormal results from prevalence of easterly gales. It is to be regretted that we have no returns this season from Mid-Atlantic, owing to Mr. Anderson's engagements in the Mediterranean. Even total absence or perfectly negative evidence of birds in Mid-Atlantic would have given us a valuable standpoint as compared with the great mortality of 1880.[7]