6 Is Vanessa Polychloros
"I have read Mr. White's paper carefully through, and I
must say that I perfectly agree with Mr. Meldola.
"The fact that the larva of V, Polychloros feeds upon elm,
whereas that of V. Urticae feeds upon nettle, would naturally
lead me to look for a mutual progenitor of these and the
numerous allied species whose larvae should feed indiscrimi-
nately upon either the tree or the weed; this we find in
V. C-album; therefore it is more probable that the group to
which the latter species belongs is the parent of both
V. Polychloros and V. Urticae than that the latter should be
derived from the former.
"The different races, or perhaps seasonal forms, of V.
C-album show considerable modifications in the outline of the
wing ; and an examination of foreign species shows that these
modifications may readily become permanent.
"I do not admit Mr. White's statement that food does not
produce variation. I have very little doubt, if he will try
the same experiment that I have done, his conviction will be
seriously shaken. Some years since my friend, Mr. Herbert
Goss, reared a number of singularly dark varieties of Odonestis
potatoria, and the only explanation for this burst of melanism
which he could suggest was, that he had been reckless as to
the species of grass upon which he fed the larvae. He sub-
sequently sent me some larvae, which I fed upon different
grass every day, with the result that I did not rear a single
typical example, all being melanic and much dwarfed. When
I gave up collecting our British moths some years since I got
rid of my specimens with the exception of a single pair,
which are now in the general collection at the British
Museum.
"Mr. White says that his V. Urticae is of the usual size,
but with the characters of Polychloros; this description would
answer very well for V. Californica, and, considering the great
general resemblance between all the species of the group, the
case is not a very remarkable instance of reversion.
"In a brood of about fifty V. Urticae, reared by me, there
was a single very dark and small specimen which, although
not like V. Polychloros, may have been a case of reversion to