Migration of Warblers. 207 



short wings and fragile bodies ; yet in the long sea 

 voyages which they make they are no less at the 

 mercy of the elements than they would be when 

 in the jaws of the most savage defile of the St. 

 Gotthard. 



While I have been fortunate in seeing so much 

 in the course of a very few days, it is obvious that 

 much remains to be discovered, and that future 

 visits to Switzerland, whether in spring or autumn, 

 may not be without their reward ; for I have little 

 doubt that there is no European region where the 

 peculiar conditions of temperature, and the extra- 

 ordinary variety of food, are so likely to produce 

 abnormal effects on the living population effects 

 which as yet are perhaps comparatively little 

 understood. I feel that my hastily collected in- 

 formation is but a single item in the vast repertory 

 of material which stands ready to the hand of any 

 one whose fortune may send him here at the right 

 time, and with the requisite qualifications. Many 

 Englishmen now pass the Alps in spring by way 

 of the St. Gotthard railway on their return from 

 Italy and the Riviera ; if among these there be 



