the prototype of V. Urticae? 8
does not affect the development of the individual, but such
individuals are treated as friends. It is to be remembered,
at the same time, that the larva of Urticae bears a much
closer resemblance to Pyrameis Cardui than to Polychloros
[specimens of larvae (preserved) were exhibited for the sake
of comparison.]
3. If it happen to be a hybrid1 between the two species, it
offers an instance of the fact which has been proved by
Darwin and others, that in the case of hybrids between
closely-allied forms the progeny, instead of assuming direct
intermediate characters, inherits the characters of one or
other of its parents; and that in numerical proportions
varying with the circumstances. As my specimen is the
only known individual of the swarm the theory is rather
a lame one.
4. Lastly, on the understanding that the specimen is the
development of an Urticae larva, we must conclude that it is
a case of recurrence to a previous form, and, if so, that form was
Polychloros; that, while Polychloros has not changed, the
change of habitat and environment has brought about the
marked variety which now constitutes a separate species in
Urticae. In favour of this supposition I may instance the
well-known fact that V. Urticae,2 like V. C-Album and P.
Cardui, varies occasionally in colour, markings, and size,
whilst Polychloros is much more persistent—indeed almost
invariable—in type, though irregular in point of size. The
latter variability, however, is common to all classes of animals
at any given period.
This persistency of type argues an antiquity beyond that
of its allies, and makes it appear highly probable that V. Poly-
chloros is the ancestral prototype of V. Urticae.
[In connection with Mr. White's paper, it may be interest-
ing to quote the following record of a similar experience
1[The Rev. G. H. Raynor records ('Entomologist' vi. 221), finding
a specimen of V. Urticae in coitu with V. Polychloros.—Ed.]
2Newman, in his 'British Butterflies,' gives woodcuts of four aberrations
of Urticae, but not one of Polychloros; nor does he instance any variation
in the latter species.