Study of the Avifauna of Lake Erie Islands. 153 



which contluued nearly every day to the culmination on September 



3, when 250 were counted in migration. During the evenings from 



August 19 until September 3, numbers could be seen flying over 



Mosquito Bay, sometimes swinging down even to Fishing Point 



and over the sand spit. The first migration followed the first chilly 



weather. 



Chdtura pelagica. — Chimney Swift. 



Common on every visit to the island, and during the entire 1910 

 study. Migrations began on August 12th and continued every day 

 to the end of our stay. There was never any marked increase in 

 numbers, but a steady southward movement. 

 ArchUoclius colubris. — Ruby-throated Hummingbird. 



Only occasionally seen among the marsh vegetation until August 

 23, after which there were decidedly more during our stay in 

 1910. At this time, as well as on the former visits to this island, 

 these birds were found feeding about the jewel weed, where they 

 were the most numerous, and where they were continually, on 

 bright days, playing antics. Single individuals migrated just over 

 the surface of the water, either passing directly down the sand 

 spit toward Middle Island, or squaring away for Middle Bass. 

 They seamed to prefer a head wind of some strength, or a quar- 

 tering head wind which rolled up considerable waves. In migrat- 

 ing they flew just over the water and dipped down between the 

 waves. I did see one bird strike out toward Middle Bass island 

 higli in the air, and did not see him settle down any. 



