116 THE ESSEX NATURALIST.
Brassica Erucastrum in Essex.—Mr. George C. Brown omits from
his recent list of "The Alien Plants of Essex" (ante., pp. 31-47) the one
plant which I had regarded as our best known Essex alien and one of the
earliest to be recorded—namely, Brassica crucastrum (= Erucastrum
inodorum and E. pollichii). This is a recognised British alien, appearing
in Mr. Druce's List of British Plants (1908), Hayward's Botanist's Pocket-
Book (13th ed., 1909), the London Catalogue (11th ed., 1925), and various
similar works.
From the foregoing one may infer that the facts of its detection in its
one Essex locality (which is, so far as I know, its only one in Britain) are
not well known. They are not recorded in Gibson's Flora of Essex (1862),
inasmuch as the plant was not detected here until after the publication of
that work. It may be worth while, therefore, to record them briefly now.
The plant was discovered, in 1864, by my old friend Mr. Joshua Clarke,
F.L.S., of Saffron Walden, growing on a large heap of sand thrown out of
a 60-ft. railway cutting during the construction of the Saffron Walden
railway. It was recorded by him in the Proceedings of the Royal Horticul-
tural Society (vol. v., p. 53) and in the Journal of Botany (iii., p. 221, 1865).
For its discovery Mr. Clarke was awarded by the Society a gold medal,
which, according to Mr. C. Roach Smith (see his Retrospections, iii., p.
114 n. : 1891), was of the value of twenty guineas. Mr. Clarke says he
found a few plants only, growing mixed with hundreds of plants of
Erysimum cheiranthoides. He adds :—"I cannot see the least probability
of its being introduced," but he does not explain how, in that case, it had
escaped notice earlier, and he remarks, somewhat inconsequentially, that
"It is one of those plants which I have no doubt will establish itself"
Mr. Clarke's views as to its nativity were contested immediately and
at some length in the Journal of Botany (iii., pp. 169-171) by Mr. W.
Carruthers, who gave an excellent coloured figure of the plant. It could
not, he urges, have been an indigenous plant newly observed in Britain,
but must undoubtedly have been introduced from the Continent of Europe,
where it is, he says, generally distributed, adding that it is found in sandy
fields and on rubbish-heaps all over France.
In later years the plant found its way somehow to the large chalk-pit
about half-a-mile outside the town on the Hadstock road, where I saw it
growing abundantly in 1879. It still grows therein ; for, only a few months
ago, Mr. George Morris and I gathered it there.—Miller Christy.