68
NOTES.
an account of finding dead fish under some such circumstance but not having the
volume at hand I can only quote from memory. Another writer also suggests
polluted water as giving rise to a phenomenon which he observed similar to that
I have noted.
Prof. Bonney has contributed an article in "Nature" on "Temperature in the
Glacial Epoch." His concluding words are : "We seem, however, fairly warranted
in concluding that, whatever may have been the cause, a lowering of [mean] tem-
perature amounting to 18°, if only the other conditions either remained constant or
became more favourable to the accumulation of snow and ice, would suffice to give
us back the Glacial Epoch." Taking two-thirds of those eighteen degrees as
representing a Post-Glacial condition of mean temperature we should probably
arrive at the stage where only one summer in a number of years was sufficient to
effectually break up the frost. This would bring us to a time of greatest erosion
of which vestiges are left as above stated. It does not seem much to ask a decrease
of twelve degrees only, yet on the other hand we must not forget that no amount
of occasional cold snaps could materially alter the mean temperature. Physical
changes of some permanency are required. We should rather lean on such a
theory as that of Dr. Croll, in which he treats primarily of. astronomical changes
which, (though small, are known to have actually occurred, and secondarily,
adducing other agencies which might reasonably be thought to have operated,
produces in the aggregate a result more than required by Prof, Bonney's figures.
Wildfowl in Essex.—I saw to-day, at Mr. Pettitt's, the following birds in the
flesh, all captured in the neighbourhood : One Whooper (Cygnus musicus), one
Mute Swan (C. olor), partly in immature plumage, and possibly an escape ; one
Canada Goose, this also may be an escape ; one Pink-footed Goose (Anser brachy-
rhynchus) ; one Bean Goose (Anser segetum), the second example Mr. Pettitt has
had this year ; one Common Bittern (Botauris stellaris), being the third specimen
this winter, including the two previously recorded ; and several female Smews
(Mergus albellus). The almost Arctic season is doubtless the cause of the appear-
ance of these interesting visitors, which we rarely see in ordinary winters. (See
also E. N, vol. iv., p. 211).—Henry Laver, F.L.S., Colchester, January 10th,
1891.
Aceras anthropophora, Br (Green Man Orchis).—A specimen of this plant
was sent to me last June by Mr. Edwin E. Turner ; he found it near Lord Ray-
leigh's park, at Terling. This is an interesting "find," as the plant has been
recorded only three times in Essex : once at Belchamp St. Paul, by Ray ; once at
Ballingdon in 1715, by Dale, and lastly in 1835 at Shoebury Common, by Edward
Foster. We may congratulate ourselves in learning that this scarce orchis still
occurs in our county.—J. C. SHENSTONE, Colchester, February 20th, 1891.
Pied Flycatcher near Harwich.—Mr. F. Kerry writes thus to the "Zoolo-
gist" for March : "On I2th May, 1890, two Pied Flycatchers (Musicapa atricapilla)
were seen in a garden at Dovercourt; and the male was shot by a boy scaring
birds. This is the first instance that I know of its having occurred in this neigh-
bourhood. I have only once before seen this species in the eastern counties ; this
was a solitary bird, some years since, at Northrepps, near Cromer, in Norfolk."
In the same number of the "Zoologist" (vol. xv., 3rd ser., p. 115) Mr. Kerry has
some interesting ornithological notes from Harwich.