280 SWALLOWS AND MARTINS 



districts, especially in the west ; but the southward movement is well maintained 

 during the first half of the month from the east and south-west of England and 

 the south-east of Ireland. By the middle of the month the emigration from Scot- 

 land and the north of England is over. . . . After the middle of October a con- 

 siderable diminution is observable except on the coast of the Channel, where the 

 efflux is maintained throughout the month . . . [and where] many departures 

 occur annually till the middle of [November], while stragglers are to be seen later, 

 especially in the south-west." It may be mentioned that part at least of the Irish 

 emigratory stream passes through the south-west of England, and the same is 

 doubtless true of the corresponding spring movement (B. A. Report, loc. cit. ; cf. 

 also B. 0. C. Migration Reports, iv. pp. 191-2 ; and v. p. 250). 



(5) Autumn return passage from Northern Europe. This takes place along the 

 east of Great Britain from mid-September onwards, but it is in great part scarcely 

 distinguishable from the previous movement. To it are probably referable the late 

 individuals so frequently recorded (even in early November) on our eastern seaboard. 

 As in the corresponding spring movement, there is a slight passage through the Outer 

 Hebrides, but no trace of any in Orkney and Shetland (cf. B. A. Report, loc. cit.). 



(6) Autumn return passage from Central Europe. This movement is a com- 

 paratively recent discovery. On 26th September and 14th October 1903, a strong 

 migration was observed at the Kentish Knock Lightship, the direction being west- 

 tvard. Very little further information has been gathered (cf. Clarke, Ibis, 1904, pp. 

 123, 138, etc. ; and Ticehurst, B. of Kent, 1909, p. 132). 



Swallows are occasionally recorded in December, and examples have been 

 known to survive an exceptionally mild winter in this country (cf. Nelson, B. of 

 Yorks., 1907, p. 156; Beeston, Zoologist, 1907, pp. 227-34, 267-71, 303-6; and 

 Harting, Field, 30th January 1892). 



The swallow's migrations are mainly diurnal, but for a notable exceptional 

 instance see B. A. Report, loc. cit. It is usually recorded as flying at a very low 

 elevation, but this may be partly a matter of the limitations of observation. The 

 swallow is, of course, markedly gregarious, and the great " flockings " which precede 

 emigration are familiar to all. Old and young usually " flock " and migrate 

 together, but sometimes in separate companies. Occasionally the great flocks 

 migrate en masse, but more often in small detachments. A strong migration takes 

 the form of a continuous stream of small and scattered bands. Although notably 

 gregarious among themselves, it is comparatively seldom that swallows are accom- 

 panied on migration by other species : the house-martin is the only frequent excep- 



