582 
Mr. J. H. Stenhouse : 
[Ibis, 
Lanins s. senator. 2 ; 1 ? juv. 
First observed in 1919 on 4 April and in 1920 on 2 April, 
after which dates the birds became numerous. A belated 
migrant was seen at Gibraltar on 23 May (the wind had been 
strong easterly for two days). They begin to nest soon after 
arrival ; a full clutch of six eggs was found in the Sierra 
Retin on 4 May. In autumn none were seen after 17 
September. 
Sylvia c. communis. 2 J ; 1 ? 
Common on migration ; not found breeding near Algeciras, 
but nests at Almoraima. First seen 27 March ; a male 
struck the lantern at Europa 29 March. Many passed 
during April. The first evidence of autumn migration was 
on 19 August, when one was found dead at Gibraltar under 
the telegraph wires; last was seen on 22 October. 
Sylvia simplex. 1 $ . 
Seen only on passage. First noted 11 April; a female 
struck the Europa lantern on 30th of that month. In autumn 
observed on passage 17 September. 
Sylvia a. atricapilla. 2 $ . 
Resident. Numbers are greatly increased during 
migration. In spring they began to pass through on 25 
February, both sexes travelling together, and passage con¬ 
tinued throughout March. Autumn migration was difficult 
to observe, but was in full swing in the middle of September 
and continued during October. Males struck the aerials on 
9 October and 22 October. It was heard in song at Gibraltar 
on 8 January. 
Sylvia m. melanocephala. 4 $ ; 2 $ . 
Resident and common. Breeds early. Noted building on 
26 February ; first egg laid 9 March. A nest watched had 
first egg laid 28 March : incubation period 13 to 14 days ; 
fledgling period 11 days. Nestlings examined had no down ; 
inside of mouth orange : flanges pale yellow. The pair were 
building their second nest on 23 May : it contained three 
eggs on 31 May. 
