1910-1911.] Bird Migration in Solway. 305 



Whereas other birds may turn up any time within a fort- 

 night or three weeks, the Landrail rarely deviates more than 

 a couple of days on either side of April 29. 



It has long been a belief of mine that the dates of arrival 

 of spring migrants are earlier along the west coast of England 

 and Scotland. That is to say, the birds are seen sooner on 

 the west coast than they are on the same latitude of the east 

 coast. So far as I am aware, the matter has not been 

 discussed yet, but it is an interesting point that might easily 

 be settled. I have reached the conclusion stated from the 

 experience of many years, and from the perusal of a multi- 

 plicity of records of bird arrivals. 



If a broad belt of bad weather intervenes anywhere across 

 the flight of a bird from its winter to its summer quarters, 

 its progress northwards is at once arrested — that is, if its flight 

 is overhead ; but if it is over the sea, the meteorological 

 influences of a bad-weather belt are not felt to the same 

 extent. Hence the extreme western flank of the advancing 

 spring migrants coming along from the French and Spanish 

 headlands has a strong tendency to get here quicker, and so 

 the dates of arrival will be earlier on the west of our islands. 



The altitude and direction of flight are two of the 

 phenomena of migration that are of prime importance in any 

 discussion of the subject. 



Skylarks and Swallows (and I include in the term 

 " Swallows " the two species of Martins) are about the only 

 birds I am acquainted with that fly at a comparatively low 

 level. Quite invariably birds that I have seen actually 

 starting on their long journey mount very quickly upwards 

 in a slanting direction till they reach a height at which they 

 can only be recognised by some special peculiarity of flight. 

 A strong beam wind will bring the birds — even those of 

 strongest powers — down to 200 to 500 feet from the surface, 

 and it is most interesting to see whole flocks with heads 

 turned almost completely to wind, and yet travelling along at 

 nearly their normal speed at right angles to their position. 

 Both in autumn and in spring I have often watched large 

 numbers passing along at heights at which there was no 

 possible chance of identification. A Gull might be dis- 

 tinguished from a Curlew, or a Wild Duck from a Cormorant, 



