Paisley Glen comprises an area of ornamental parkland and mixed woodland on the outskirts of Paisley, about 15 km from Glasgow. While birdwatching there at 14.00 GMT on 17th June 1977, TB's attention was attracted by an unfamiliar song in an overgrown part of the glen. On locating the singer, he was immediately impressed by its combination of exotic coloration and warbler jizz, a combination which suggested to him that the bird was a species of American wood-warbler (Parulidae). TB kept the bird under observation until 15.30 hours, while he took field notes, and then left to fetch tape-recorder and photographic equipment. Twenty minutes after returning, he relocated the bird, again by song, and at 16.30, after taking photographs and recording its song, he informed HG of the bird's presence. From 17.30 to 18.30, we kept the bird under observation while taking field notes; during this time, viewing conditions were excellent, with little wind and low, flat sunshine. On comparing our notes with the text and plates in Peterson (1947), we quickly became convinced that the bird was a male Cape May Warbler Dendroica tigrina in breeding plumage. The bird was confiding and allowed itself to be approached down to 4½ m while it fed and sang among the trees and scrub. So frequently did it sing at this stage that we were both of the opinion that it had taken up territory and would probably stay for some time; unfortunately, this was not to be.