]()2 TiiH Wilson Bult.etix — Xo. 71. 



settlements. The iiietlian date of arrival is April 10. and the latest 

 fall record is September 30, 3907. The Martins leave the vicinity 

 of their breeding places before the first of Augnst. A roost of sev- 

 eral hundred was studied on North Harbor island August S, 1903, 

 and a great migration from Pelee island across to Marblehead, Au- 

 gust 31 and September 1. 1905. On September 1 the migration 

 stream was followed southward past Middle to Kelley's island, 

 where the birds were gathering in clouds preparatory to roosting 

 in the woods near the west end of the island. At twilight they 

 were whirling above the woods in a mighty maelstrom, the vortex 

 of which was over the woods and the spreading top covering the 

 entire island. Arrivals from the direction of Pelee island were 

 continually swelling the host. The maelstrom form had not 

 changed when darkness settled down, making further study im- 

 practicable. On August 29, at Pelee island, the Martins were pass- 

 ing at the rate of five a minute from 4:20 p. m. until as late as 9 

 p. m. With them were groups of Barn, Cliff, Bank, and Rough- 

 winged Swallows, and an occasional Chimney Swift. The wind 

 ••vas west-south-west, brisk, and all of the birds were headed nearly 

 due south-west, or toward Put-in-Bay island rather than toward 

 Middle or Kelley's ; but all invariably drifted south so that they 

 passed either over or to leaward of Middle. On August 30, an early 

 morning thunder storm apparently checked a migration which had 

 barely started. After the storm scattered flocks of Martins and 

 Barn Swallows passed over the course of the previous day. At 

 4 :.S0 p. m. the flight began again and continued well into the night. 

 Swallows were more numerous and moved more directly south 

 without side excursions after insects, and faster. They seemed 

 nervous and somewtiat anxious. A flock of Red-winged Blackbirds 

 passed southward over the course, and occasional Nighthawks 

 drifted southward as they fed. On September 2, when the Martins 

 were again migrating in considerable numbers, we sailed eastward 

 into the lake, passing between Kelley's island and Marblehead. 

 where birds were crossing southward, then out eastward, reaching 

 Vermilion at dark. We thus crossed any line of flight from Point 

 Pelee to the mainland in a direct line, but no birds were seen cross- 

 ing except between Kelley's and Marbleihead. It seems to me sig- 

 nificant that all of the migrating Martins passed down the east side 

 of Pelee island. We found no evidence of a roost on the island. 

 The most of them were not above 300 feet above the lake, except 

 when they were circling over Kelley's island. 



179. PetrochdidoH hiiiifroiis. — ^Clift" Swallow. 



It is listed as a common summer resident by McCormick and 

 Wilder (MS.), which applies to conditions prior to 1S90. There 



