246



Correspondence, Notes, etc.



SEXUAL DIFFERENCES.


Sir, —Being asked recently, as I often have been before, how to dis¬

tinguish the sex of the European Goldfinch, it occurred to me that I might

perhaps get hold of better characters than those usually given, by comparing

properly sexed examples and expanded wings of the same. Unfortunately

I only possess one hen in the skin, and this exhibits the remarkable

character of brown upper tail-coverts!


So remarkable a distinction from the colouring of the tail-coverts in

male Goldfinches determined me to examine the series of skins in the

British Museum. The following sexual differences are the result of my

comparison of skins and wings :—


The male varies in size more than the female, as I well knew; one of

my living examples being indistinguishable in size and colouring from

normal Siberian specimens, though I purchased it as a Greypate from a

bird-catcher, who netted it in Kent: at the same time the average cock

Goldfinch is distinctly larger than the average hen, and has decidedly

longer wings: the greater length being due chiefly to the better develop¬

ment of the second, third, fourth, and fifth primaries (counting from the

front of the wing in the old style).


All the colours are brighter in the cock bird, the black of the wing

being distinctly deeper and more glossy; the yellow belt of a narcissus,

rather than primrose, colour. On the secondaries the 3 r ellow belt is broad

throughout ; it narrows somewhat on the inner secondaries, but it is not

clouded as in the hen. The upper tail coverts in the cock bird are

invariabl) T white, more or less washed with buffish-sienna; those of the

hen vary considerably; being, however, always distinctly browner than

those of the cock bird.


All the white portions of the plumage are purer in the cock, the

cheeks especially being much less stained with brownish : the blaze or mask

is of a brighter crimson in the cock, but its extent appears to differ very

slightly, and I think not constantly.


The form of the beak is very different; that of the male being much

wider at the base and tapering much less gradually than in the hen, though

slightly longer.


After examining the Goldfinches at the Museum, I thought it might

be useful to look at the various groups of Starlings, to see whether they

approached most nearly to the Thrushes or the Crows in their sexual

differences. I found that, in total length, and in the relative formation of

their bills, the sexes correspond with the Thrushes ; only these sexual

characteristics are far less marked, and in Spodiopsar they are barely

distinguishable ; a series of expanded wings would probably show more

marked differences.



A. G. Butler.



