THE MIGRATIONS OF THE SWALLOW 195 



ness of migration there as compared with that on the 

 west coast. 



In Shetland and Orkney there are only slight and 

 irregular appearances of these returning Swallows of 

 passage, and but feeble evidence of their taking the 

 Hebrides on their return journey, though the records 

 indicate such a transit during September and the first 

 days of October. There are passage movements on the 

 part of Irish birds discernible in the south-west of 

 England to the third week of October, with occasional 

 stragglers to the middle of November. 



It has been already remarked that after their arrival 

 on our shores, Swallows on autumn passage mix with 

 our native birds then emigrating, and it is no longer 

 possible to trace the former, though they doubtless form 

 the bulk of the rearguard movements of the autumn. 



Auhiinn Passage from Western Europe by East-to- 

 West Route. — During my sojourn in the Kentish 

 Knock lightship in the autumn of 1903, I was much 

 interested to observe Swallows coming from the east 

 and flying towards the coasts* of Essex and east Kent. 

 Such flights were witnessed on seven occasions between 

 26th September and i6th October. These migrants 

 from the opposite shores of the North Sea passed the 

 ship in parties composed of young and old, and were 

 timed between 8 a.m. and 2 p.m. Spring passages, in 

 the reverse direction, do not appear to have come 

 under notice. 



In September Swallows are recorded at the light- 

 ships off the mouth of the Thames and the Kentish 

 coast as coming from the south-east, occasionally in 

 considerable numbers. This would seem to imply that 

 they were leaving the French or Belgian coasts, perhaps 



