REPORT OX THE MIGRATION OF BIRDS. 381 



sioii a special (leclaratioii for "birds'' in general can claim no scientific 

 A'alue. Such genei'al expressions are to be avoided, becanse tliey may 

 easily lead astray. 



As already remarked, the \ iew of Ihe existence of geograpiiically 

 defined routes of migration began to prevail gradually, and almost 

 simnltaneously with the completion of the writer's work similar state- 

 ments appeared from the most a]>])roved qnait<'rs, for example, from 

 ^Vallace and A. von Midden(h>rff. The writer can not omit to mention 

 that in a personal interview he received the fall approbation of the last- 

 named veneral)Ie in\'estigator of Siberia. The ap])roval of Ang. Weis- 

 mauu may be regarded as of great importauce with regard to 'MvMogj 

 in general, and tinally, Radde's well-known statemeut "that every- 

 where on earth the direction of the migration intinmtely depends, and 

 is even dictatorially conditioned, on the relief of tlie laiul which the 

 birds pass" (1884). 



For the continued investigation of the phenomenon of jnigration in 

 the sense above mentioned, it seemed absolutely necessaiy to obtain a 

 large quantity of obsei-vations from the most different places. For in- 

 definite acccmnts of the oceniTence of the species of l)irds in greater 

 districts permitted no reliable conclusions regarding the local extent 

 of the migration routes. It rather seemed desirable to obtain immer- 

 ous observ*ations on the migration, repeated eveiy year. Just as is done 

 in the study of meteorological ])henomena. 



For these reasons Mr. Keichenow. at the spring me<'ting of the Uni- 

 versal (xerman Ornithological Society in Brunswick, on May !il*, 1875 

 {Journ.f. Ornlt/i., 187."), p. .'U7), ])(>inted to the necessity of collecting 

 observations on the migration of birds according to a uniform plan in 

 diverse regions. It was then referred to a committee to })romote the 

 inquiry. 



The calling into existence of this committee for obser\ation stations 

 ofthebiids of (iermany is known to the world; as also its annnal 

 reports, which have appeared since tlie year i87(> in ever increasing- 

 size, and whose editing has icllected the greatest credit on Prof. 11. 

 Blasius and Prof, A. ]\eichenow. It is also fnrtln'r known how this 

 example of (Iermany found imitators in Austria-Ilnngary, the observa- 

 tions made there being first (1880, 1881) lecei vcd in the CJernnm 

 reports, then from the year 1882, a])peai'ing indei)endently. 



Every ornithologist is also acquainted with the progress of develo])- 

 ment of this question in (ireat Britain, where observations were begun 

 from the year 1879, especially in the light-houses, and published an- 

 nually. 



lndei)en(lentl\- of these elforts, investigations of faunas of dirCerent 

 small ami large tracts, as well as of general migrations, were started. 

 More will be said further on about these, as well as about the magnifi- 

 cent arrangements in North Anunica, 



So far had the ([uestion advanced when, in Api'il, 1884, the First In- 

 ternational Ornithological Congress met in Vienna and gave a i)ower- 



