250 BRITISH BIRDS. 



Mr. Stanley Duncan and I came to the conclusion, after 

 careful comparison, that the bird was a variety of Ligurinus 

 chloris. 



The coloration of the Greenfinch is, I suppose, produced 

 by the combination of a yellow with a darker (perhaps black) 

 pigment, modified by the overlying structural peculiarities 

 of the feather. One might suppose then that the loss of the 

 darker pigment (a partial albinism), with or without modifica- 

 tion of the feather-structure, might produce a result not 

 unlike the sj^ecimen in question. M. Winzar Compton. 



NORTHERN BULLFINCH IN YORKSHIRE. 



Mr. T. H. Nelson informed me that in November Bullfinches 

 were reported to him from one or two places on the Yorkshire 

 coast, but specimens were not forthcoming. On December 

 4th, 1910, however, I received from a correspondent on the south 

 Yorkshire coast a typical male of the Northern Bullfinch 

 {Pyrrhula p. pyrrhula) which had been shot there on the 

 previous day. Only two examples have been previously 

 recorded from Yorkshire (November, 1894), but I think 

 it probable that the immigrations noted in the Birds of 

 Yorkshire (Vol. I., pp. 194, 195) under " Pyrrhula europcea " 

 in various years, and notably in November, 1880, and 

 October and November, 1884, 1886 and 1887, were referable 

 to P. p. pyrrhula. No British specimen of the continental 

 P. p. europcea has as yet, I believe, been identified. 



H. F. Witherby. 



THE CROSSBILL IRRUPTION. 

 A LARGE number of correspondents have very kindly sent 

 information in answer to my questions on p. 186 with regard 

 to the departure or continued presence of the Crossbills. 

 I hope my correspondents will accept my thanks here expressed 

 and will forgive me if I do not acknowledge their letters 

 individually. In a future number I hope to summarize all 

 the observations published and unpublished. — H.F.W. 



Crossbills nesting in Bedfordshire. 



Mr. J. Steele Elliott records {Zool., 1910, p. 472) that he 

 found an overthrown nest, apparently belonging to a Crossbill, 

 on May 6th, 1910, at Sutton, Bedfordshire, and that he saw 

 recently fledged young being fed by old birds at Sandy on 

 May 8th. 



EGG-DAUBING BY THE JACKDAW. 



With reference to the notes on this subject {antea, pp. 176 and 

 214) I may record that some twelve years ago Mr. John Palmer 



