THE WHITE-BACKED WOODPECKER NOT A BRITISH BIRD. 401 
(which, I may remark by the way, are characters separating it as 
widely from D. leuconotus as from any other species known to 
me). Next to these are the indistinct streaks in the sides of the 
belly and flanks, and the pale red of the vent. Mr. Seebohm has 
kindly shown me two specimens shot in Heligoland in October, 
1876, out of a band of visitors similar, no doubt, to that which 
appeared in Shetland in the autumn of 1861. Both these are, 
like Mr. Gurney’s, birds of the year,—a fact proved not only by 
their red heads, but by the first primaries, which among Wood- 
peckers seem to be always larger in the young than in adults,—and 
both of them exhibit (though one much more than the other) the 
indistinct iliac streaks and the pale red of the circum-anal region. 
But both of these birds have always been accounted specimens of 
D. major, the ordinary plumage of which they in other respects 
entirely match, and I think he would be a bold man who would 
venture to refer them to any other species. * 
Accordingly it comes to pass that the only points in which 
Mr. Gurney’s bird differs from examples of D. major are the 
before-mentioned grey upper wing-coverts and hind-head—for 
I should perhaps have mentioned before that in size it agrees 
absolutely with that species. Undoubtedly these parts ought to 
be black, but, when we know that albinescence, or canescence, is | 
the effect of a physiological process from which there is reason 
to suppose that no birds are exempt, though itis much commoner 
in some groups than others, I think it is but right to ascribe the 
abnormal appearance of Mr. Gurney’s bird to this cause; and 
hence I wholly subscribe to the opinion delivered more than ten 
years since by Messrs. Dresser and Sharpe, namely, that the bird 
shot at Halligarth, in Unst, on the 3rd of September, 1861, by 
the late Dr. Saxby, the skin of which is now in Mr. J. H. Gurney’s 
collection, is a variety of the Greater Spotted Woodpecker, 
Dendrocopus major. 
20th August, 1881. 
* Indeed Naumann (Vo6g. Deutschl. v., p. 302) describes the young of 
this species as streaked with blackish on the thighs and flanks. 
