FIELD STUDY IN OKNITHOLOGY. 473 



B*R1) MIGRATION. 



On the solution of the probh'ui of the migration of birds, the most 

 remarkable of all the phenomena of animal life, mueh less aid has been 

 contributed by the observations of held naturalists that miglit reasona- 

 bly have been expected. The facts of migration have, of course, been 

 recognized from the earliest times, and have afforded a theme for 

 Hebrew and Greek poets three thousand years ago. Theories which 

 would explain it are rife enough, but it is only of late years that any 

 systematic effort has been made to classify and summarize the thou- 

 sands of data and notes which are needed in order to draw any satis- 

 factory conclusion. The observable facts may be classified as to their 

 bearing on the whither, when, and how, of migration, and after this we 

 may possibly arrive at a true answer to the Why? Observation has 

 sufficiently answered the first question, Whither? 



There are scarcely any feathered denizens of earth or sea to the 

 summer and winter ranges of which Ave can uot now point. Of almost 

 all the birds of the holo-arctic iauna, we have ascertained the breed- 

 ing places and the winter resorts. ISfow that the knot and the sander- 

 liug have been successfully pursued even to Grinnell l^and, there 

 remains but the curlew sandpiper ( Tringa s)(har<[)i((ta), of all the known 

 European birds, whose breeding ground is a virgin soil, to be trodden, 

 let us hope, in a successful exploration by Nansen, on one side or other 

 of the Xorth Pole. Equally clearly ascertained are the winter quarters 

 of all the migrants. The most casual observer can not fail to notice in 

 any part of Africa, north or soutli, west coastor interior, the myriads of 

 familiar species which winter there. As to the time of migration, the 

 earliest notes of field naturalists have been the records of the dates of 

 arrival of the feathered visitors. We possess them for some localities, 

 as for Norfolk by the Marsham family, so far back fls 1736. In recent 

 years these observations hnve been carried out on a larger and more 

 systematic scale by Middendorf, who, forty years ago, devoted himself 

 to the study of the lines of migration in the Russian Empire, tracing 

 what he called the isopipfescs, the lines of similtaneous arrival of particu- 

 lar species, and by I'rof. Palmen, of Finland, who, twenty years later, 

 pnrsued a sinular course of investigation; and by Prof. Baird on the 

 migration of North American birds ; and subsequently by Severtzoff as 

 regards central Asia, and Menzbier as regards eastern Europe. As 

 respects our own coasts, a vast mass of statistics has been collected by 

 the labors of the migration committee appointed by the British Asso- 

 ciation in 1S80, for wiiich our thanks are due to the indefatigable zeal 

 of Mr. John Cordeaux and his colleague Mr. John Ilarvie Brown, the 

 originators of the scheme by which the hght-houses were for nine years 

 used as posts of observation on migration. The reports of that com- 

 mittee are familiar to us, but the inferences are not yet worked out. I 

 can not but regret that the committee has been allowed to drop. Prof. 



