REPORT ON THE MIGRATION OF BIRDS. 191 
Rhuvaal forty to fifty were seen, as related above. Swallows 
appeared to migrate principally when the wind is southerly 
(S.W. to 8.I.), in light, variable, or fresh head- or side-winds, 
and hazy weather. Exceptions are found, however, at Dhuhear- 
tach on July 26th, when the wind was N., fresh, and weather 
clear; and at Skerryvore on Aug. 17th, when one appeared at 
the lantern about 10 p.m. (two hours after lighting up) in a N.W. 
light breeze, with showers. Swallows migrate mostly by day, 
resting all night. My returns show that they passed at all hours, 
but mostly before dark. 
Martin, Hirundo urbica.—Martins are noticed at two stations 
only, viz., Butt of Lewis and Corsewall. The migration lasted 
between July 29th and Aug. 16th, or during eighteen days (but 
data are defective). They travelled during the day, resting around 
the lighthouses at night, with S. to S.E. and S.W. winds; the 
only one killed was when wind was N.N.E., at Corsewall. 
Wren.—The records are few of this species: usually noticed 
on migration in large numbers; they appeared at Monach Island 
and Dhuheartach. The earliest date is Aug. 17th, when “some” 
struck at 10 p.m., and between that and 3 a.m.; wind W., and 
haze. The latest date is Dec. 9th, when one was seen at 3 p-m., 
with S.W. breeze, and showers. In fourteen years Mr. Edgar 
never saw a Wren at the Butt of Lewis lighthouse. 
Goupcrest, Regulus cristatus.—At Mull of Galloway on July 
18th, alighting all night and resting. Mr. Edgar's letter of 20th 
Sept. supplies the information that he has never seen Goldcrests 
at the Butt of Lewis—a negative fact of value in tracing their exact 
lines of flight. Perhaps in our next reports observers will state 
in their remarks if any of the species noticed in this one have 
hitherto been rare, or entirely absent from their stations in past 
years. 
Rogin.—Appeared at Kyleakin, and thence southwards at 
Skerryvore, Rhuvaal, Skervuile, Rhinns of Islay, and Corsewall. 
The largest number recorded at Corsewall, where fifteen struck 
on Sept. 15th, at 11 p.m.; wind S.W., light breeze, and haze. 
The earliest date is Sept. 10th—one at Skervuile, at midnight ; 
wind S.W., light, and cloudy. The latest is at Rhuyaal, on Dee. 
4th at 9 a.m., when one was seen; wind variable, light breeze, 
clear. Thus, time occupied is between Sept. 10th and Dee. 4th. 
A rush took place in September between 10th and 21st, but no 
