SAXICOLA GENANTHE. 403 



Mr. Dresser remarks thus Q Birds of Europe/ part xxxi. p. 9) :— 

 " Ornithologists Uving on the south coast of England say that the birds 

 which arrive first vary in size from those which arrive later ; but I find that 

 the size of examples from various localities varies considerably, those from 

 Greenland being the largest, whereas specimens from Palestine and some 

 from Egypt are the smallest, intermediate forms being found from localities 

 in various parts of Europe." 



All the birdstuff^ers here, and many of the birdcatchers, know the 

 difference between the large and small Wheatears ; and Macgillivray (vol. ii. 

 p. 292) says ''individuals are seen of much larger size than others." 



The smaller race comes first, perhaps about March 3rd (malesj, and 

 females about March 10th; for the sexes do not travel together. 



The larger race arrives about April 13th (males), and females 

 April 24 th. 



The dates, of course, depend a little upon the year; but the space 

 between is constant. 



After careful reflection I construe the thing thus : the small birds are 

 probably British-born, the large ones most likely Northerners. 



Thus we have a very great difl^erence in size between the larger conti- 

 nental birds, called here '' Dutch Larks," and the smaller ones of English 

 origin. This is known to almost every one who owns nets ; they can tell 

 them in the dark. The two races keep distinct. 



Again, we have the larger Ring-Dotterel and the smaller; but here I 

 am quite at a loss to account for a fact the converse of the case of the 

 Wheatears, that the large birds come first and the smaller ones last. But 

 in all three species — Sawicola oenanthe, Alauda arvensis, and C. hiaticula — the 

 times of arrival of the large and the small are different. 



I suspect that, if it could be known, most birds vary in the same way. 



