■883. 



Grundtvig on Warblers of Wisconsin. 6^ 



northerly wind again rising, appeared to partially check this vast 

 throng ; but May lo, after another hard rain, I noticed them again 

 moving slowly northward. The new species observed during 

 this flight were Myiodioctes canadensis^ Dendrceca striata^ and 

 Geothlypis trichas. The wind once more shifted to the south, 

 and on the i8th I noticed a few new flocks, among which were 

 some Dendrceca castanea. May 3i was the only day after the 

 15th when the number of flocks exceeded those previously ob- 

 served. The night of the 30th was exceedingly cold, freezing- 

 hard in many places ; in the morning, a very strong south wind 

 was blowing, and Warblers in innumerable flocks began arriv- 

 ing. Helmlnthophila pereg'rina^ previously seen but once 

 (May 19), now arrived in large numbers. This immense 

 flight soon ceased, and by May 26 only a few single Warblers 

 were noticed. 



The number of Warblers that migrated over this route was 

 simply astounding. Some of the more uncommon eastern spe- 

 cies appeared here in large numbers. I found at the least estim- 

 ate several hundred of HehnintJiophila celata., and to say I 

 observed several thousand of Dendrceca tigrina would not be 

 overstating it. This passage of the Warblers was really the most 

 interesting of the kind I have ever witnessed. No bird migra- 

 tions in Europe can be compared with it. The many pleasant 

 hours spent in my boat, studying these graceful creatures, mani- 

 fold both in species and beauty, will long be cherished among 

 the many recollections of my sojourn in America. 



The following is my annotated list of all the Warblers observed, 

 omitting the genus Siurus^ members of which were never noticed 

 in company with the other species. 



IMniotilta. varia (^O V. May i two males were taken, not 

 in flocks with other Warblers, but east of the Wolf River. 

 Afterwards I found it usually associated with other Warblers, 

 Kinglets or Titmice, but five were the most I ever counted in any 

 one flock. A few remained to breed. The first female was taken 

 May 10. 



Parula americana (Z.) Bp. May 3 two females were 

 taken. The next morning a few others of both sexes appeared 

 in the other flocks, no more than three being noticed together ; 

 but in the afternoon they were quite numerous. May 5 I noticed 

 these Warblers in small flocks by themselves, but during the next 

 few days they were rather scarce. Between the I3th and the 



