208 ON BIRDS FROM THE NETHERLANDS, 
Uria troille (L.) var. ringvia Briinnich. 
This winter we purchased two examples of the ringed 
variety, both in winter dress and both males, shot 8 Novem- 
ber 1909 and 31 January 1910 near Texel. 
Cepphus grylle (L.). 
The black guillemot is a very rare straggler to our 
coast; only two specimens were known to have been ob- 
served, viz.: the specimen, mentioned by Temminck and that 
found in December 1904 near den Helder. This winter I 
received two specimens, both males in winter dress, which 
were killed on the Marsdiep near Texel, 27 December 
1909 and 1 January 1910. 
Apus apus (L.). 
On the 24th of August I received a young male, that 
had been shot the day before near den Helder. On the 
14th of September 1908 I observed at Lekkerkerk, Zuid- 
Holland, a single specimen among a flock of swallows. 
Cuculus canorus L. 
I received two females in the rufous phase of plumage, 
shot 21 May 1910 near Breda and 18 June 1910 near 
Wassenaar. The oviduct of the latter bird contained a fully 
developed, but broken egg. 
Motacilla flava thunbergi Billberg. 
Motacilla flava borealis Sundevall, Notes Leyden Mus. XXX, 1908— 
1909, p. 200. 
At the 19th of May I received three yellow wagtails, 
caught the day before at Harderwijk, of which a male 
belongs to the northern form thunbergi, and the two other 
ones, females, to the typical form. At the 21st of May 
I received again 17 yellow wagtails, caught 20 May near 
Notes from the Leyden Museum, Vol. XXXII. 
