the prototype of V. Urticae? 5
V. C-album............. Europe, N. and W. Asia.
V. I-album ............ Asia Minor, S. Europe.
V. V-album............ Asia Minor, S.Europe.
V. Californica......... California.
V. Polychloros......... Europe, Asia.
V. Xanthomas ...... E. Europe, N. India.
V. Cashmirensis ...... N. India.
V. Urticae ............ Europe, W. Asia.
V. Milberti ............ S. America.
These were only a few of the more striking transitional
forms selected for the purpose of illustrating the argument.
In the language of evolution we should therefore say that
the genus Vanessa was in a very complete state of phyletic
preservation, i.e., all the species having diverged from a
common ancestor, the various steps in the process of diver-
gence, instead of having become extinct and leaving large
gaps between the species, as so frequently happens, have
been more or less preserved down to the present time. Poly-
chloros, Xanthomelas, Urticae, &c, are thus true blood-relations,
and, in accordance with the laws of heredity, it is not there-
fore surprising, although extremely interesting, that we
should find one of these species occasionally giving rise to a
variety resembling an allied form. If, therefore, Mr. White
means to ask whether Polychloros is the progenitor of Urticae
on the strength of his having obtained a variety of the latter
resembling the former, he (the President) would be inclined
to answer that the two species under consideration, with their
congeneric forms, had all descended from a common ancestor,
and that the variety in question was a case of reversion to this
ancestral type.
In illustration of the foregoing remarks the President
exhibited specimens of Urticae and Polychloros, with the inter-
mediate North Indian V. Cashmirensis, and, as a parallel case,
Pyrameis Atalanta and Cardui, with the intermediate P.
Callirhoe, likewise from N. India.
[Mr. A. G. Butler, F.L.S., F.Z.S., of the Zoological
Department, British Museum, has kindly furnished the Editor
with the following valuable observations on the above :—