546 bulletin: museum of comparative zoology. 



3. Sharp-tailed Grouse. 



4. Cooper's Hawk. 



5. Red-tailed Hawk. 



6. Duck Hawk. 



7. Black-billed Cuckoo. 



8. Ruby-throated Hummingbird. 



9. Phoebe. 



10. Alder Flycatcher. 



11. Hoary Redpoll. 



12. Lapland Longspur. 



13. Northern Shrike. 



14. Nashville Warbler. 



15. Tennessee Warbler. 



16. Bay-breasted Warbler 



17. Blackburnian Warbler. 



18. Pine Warbler. 



19. Canadian Warbler. 



20. Black-throated Blue Warbler. 



3. Birds rare in Labrador but fairly^common in Newfoundland. 



1. Black-capped Chickadee. 



2. Olive-sided Flycatcher. 



3. Black-throated Green Warbler. 



4. Great Horned Owl. 



5. Redstart. 



6. Winter Wren. 



A feature of as much interest as the gaps in the Hst of species is the 

 large number of geographic forms recognized, eight in this paper. 

 But there are at least twice as many species in Newfoundland which 

 show a tendency toward darkness. Here, in Newfoundland, one 

 can observe bird-races in the making! It is impossible to say whether 

 this darkening of the coloration is an acquired character induced by 

 the humidity and bleakness of the country, or whether the environ- 

 ment is one which fosters all variations towards darkness, which 

 variations may themselves have arisen independent of the environ- 

 ment. No matter where the truth lies, these tendencies exist, and 

 in these Newfoundland birds, we have represented the very beginning 

 of future geographic forms. 



In the preparation of the following notes, I have received the ever 

 generous aid of Mr. Outram Bangs. Mr. William Brewster has 

 loaned specimens for study. Information in regard to the Labrador 



