The second discrepancy of habit which must be" noticed
is one that will weigh heavier with many naturalists, and yet
it seems really to have hut little significance. Throughout
the greater part of the British Islands the Black Crow, where
it occurs, is mostly a summer-visitant, while the Grey Crow,
in England at least, is, as a rule, an autumnal immigrant,
appearing regularly in the fall of the year, and disappearing
as regularly in spring. But then we have to consider the
general principle of migration. Whatsoever its cause may be
and howsoever it may he effected, its process is undisputed.
In the northern hemisphere as summer wanes all birds
subject to its influence move in a generally southward
direction. Now Crows, whether Black or Grey, notoriously
belong to this category and shift their quarters accordingly.
In Great Britain, and to a certain extent elsewhere, the
Black Crow occupies a more southern range than the Grey
Crow. This relative position is preserved irrespective of
season. Each follows the sun towards the equator and
each moves northwards as the sun returns towards the pole,
so that both are impelled by precisely the same movement*.
We know how with many kinds of birds our native stock
emigrates more or less entirely towards autumn, and its
place is taken by an influx of northern strangers. In
some species the most practised eye can detect no difference
between its indigenous and its foreign members; but in
others such a difference is easily discerned. In the Crow
the difference is wider perhaps than in any, but the difference
is only of degree, it is quantitative and not qualitative.
Hence, while the discrepancy affords us no proof that the
Grey and Black Crows are specifically distinct, it furnishes no
good ground for asserting that they are specifically identical.
In other respects the habits of the two forms defy differentiation.
Their food, cries and mode of nidification, their
rapacity, wariness and conduct generally are absolutely alike;
and their geographical distribution, which offers many points
of interest, alone remains to be considered. In the British
Islands it may be said that the Black Crow breeds, if per-
* This has been admirably put by Mr. Hancock (ut supra).
mitted by gamekeepers, more or less commonly throughout
England and Wales, to the almost total exclusion of the
Grey Crow—the instances in which the latter, unaided by
the former, has been known to build its nest south of the
border being very few in number*. Beyond this limit,
however, the case is altered, and almost at once the Grey
becomes the commoner form, for, though the Black Crow
holds positions, apparently in the low-lying districts, even
far to the northward!, its numbers hear no comparison with
those of the other throughout Scotland generally, where both
are almost universally called “ Huddies ”—a name corrupted
from Hooded Crow, and therefore properly belonging to the
parti-coloured birds—the whole-coloured birds being distinguished
as Black Huddies. Indeed so much do the two
forms intermingle that in many parts of the country the
notion prevails that the difference in plumage is due to sex.
So long ago as 1828 Fleming described the female of Corvus
* The Editor learns from Mr. More that it is supposed to have done so in
I)evon, but its rarity in that county at any time casts suspicion on the story.
Mr. Haver informed Dr. Bree that some used to breed every year near the Black-
water, in Essex; but it would seem that this is not so now. In Norfolk a pair
is said by Hunt (Br. Orn. ii. p. 43, note) to have reared a brood in 1816 nea
King’s Lynn ; what looked like a young bird was seen near Yarmouth in July,
1843 (Zool. p. 316), and others near Cro'mer in August, 1867 and 1877
(Zool. s.s. p. 1012, and 1877, p. 443). In Lincolnshire, Mr. Cordeaux shot a
partly-fledged example August 5th, 1873 (Zool. s.s. p. 3685). I t has been
observed twice, or oftener, near Flamborough under circumstances which presume
its breeding there (Zool. p. 6142, s.s. pp. 2728, 5081). Williamson
declared (P. Z. S. 1836, p. 76) that it had bred on two or three occasions near
Scarborough, but the only instances of which he gave details shew that one of
the parties to the union was a Black Crow. I t was also reported to Mr. More
as breeding regularly in Cumberland, and occasionally in North Wales ; but
confirmation is needed in either case. That it does so, however, annually in the
Isle of Man seems to be established.
t Mr. More obtained evidence of its breeding regularly in all the counties
south of the Firths of Forth and Clyde, and northwards in those of Dumbarton,.
Argyle, Clackmannan, Perth, Aberdeen and Banff—occasionally also, it would
seem, in Caithness and (if it has not been confounded with the Rook) in some
of the Hebrides, but whether in all these localities it breeds unpaired with the
Grey form, is ' open to doubt. St. John says that in Moray it is impossible to
decide on the line which divides the two birds, though the Grey Crow is so much
the commoner as to be the Crow of the country, and that he never saw there
a pair of perfectly Black Crows (Nat. Hist, and Sport in Moray, p. 58).
VOL. I I. 0 a