3j^ THE SCOTTISH NATURALIST 



given so freely of their time and labour in the work of ringing 

 birds. Our best thanks are also due to correspondents who 

 have sent us information regarding the reappearance of 

 marked birds. Special acknowledgment is due to my friend 

 the late Mr Lewis N. G. Ramsay, M.A., B.Sc, who for a 

 second time took most of the central work of the Inquiry 

 upon his shoulders during some months in which I was 



absent. 



It is unnecessary to repeat any of the description of 

 methods and routine given in our first report, but certain 

 changes must be recorded. Previously we had allowed our 

 co-operators to mark birds almost indiscriminately ; but we 

 have since felt that the work could be increased in value by 

 concentration on a few selected species, while at the same 

 time a great economy of labour would be effected. Various 

 factors have influenced our selection of species for con- 

 centrated attention. Three qualities are necessary in a 

 species for it to be a good subject for our method. In the 

 first place, it must be procurable for ringing in large 

 numbers ; secondly, it must afford a fair percentage of re- 

 appearance records; and thirdly, its migratory movements 

 must be of sufficient interest to repay close investigation. 

 Unfortunately many of the small passerine birds — including 

 some of our most typical migrants — which would head the 

 list under the third category, have been found altogether 

 wanting under the second. On the other hand, all Gulls, 

 which rank highly under the first and second heads, are, with 

 the exception of the Lesser Black-backed Gull, deficient in 

 the third respect. The Lapwing stands very well as regards 

 all three counts, while the Blackbird, Song-thrush, and 

 Starling also rank fairly high in each. It is owing to 

 prominence under the second head that the Mallard and 

 Woodcock are included, while the Swallow and the Herring- 

 gull owe their present retention in great part to our 

 possession of a large stock of rings of the appropriate 

 sizes. 



Owing to the limited space available in a magazine like 

 the Scottish Naturalist, we have, in deference to the wish of 

 the editors, treated the subject as concisely as possible, and 



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