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A. Funestus, A. Minimus, A. Rhodesiensis, and the Italian species A. Superpictus
(Grassi).

       We thus have at least nine closely allied species of this one group which,
although considered by entomologists to be quite distinct, are nevertheless
very difficult to identify and to separate from each other. The points relied
upon by Mr. Theobald* for separating all the above mosquitoes from each other
as distinct species are as follow :—

          (1) Differences in the characters of the wing markings.

          (2) Differences in the relative position of the transverse veins of the wings.

          (3) Differences in the character of the male genitalia and of the fore
                ungues of the male.

       (1) The wing markings of the nine species mentioned above are admitted
to be almost identical, and in forming an estimate of the value to be attached
to slight differences in wing markings we must remember that if only a small
number of any one species of anopheles are examined, considerable variations
in the wing markings will be found. Indeed, it is quite possible that in some
species at any rate a seasonal variation in these markings may occur. These
variations have not previously been taken note of by entomologists in England,
owing to the limited supply of specimens to which they have access, and as
several of the so-called new species (e.g., A. Indica, and A. Minimus) have been
described from only a single specimen, it might easily happen that such a spe-
cimen was a variation from the type of an already described species.

       Some of the variations that occur in wing markings will be mentioned in
the notes on the different species, and on the whole I am of opinion that such
slight differences as are recorded between the wing markings of the species
enumerated above, are of little or no value as a means of separating them into
distinct species.

       (2) Great stress is laid by Mr. Theobald on the value of the relative posi-
tions of the cross veins of the wings as a means of distinguishing species, and
a reference to the monograph will show that this is the chief character by which
he separates nearly all the species of this group. Thus of A. Funestus he
says, "It is clearly related to A. Rhodesiensis and A. Superpictus, but it can
be readily told by the positions of the cross veins." Of A. Indica he says,
"It is seemingly related to Grassi's A. Superpictus, the wings, etc., being
almost identical ......... From A. Funestus it differs in the position of the cross
veins." Of A. Rhodesiensis he says, "At first sight one would take it for
Grassi's A. Superpictus, but the position of the cross veins at once separates
them." Of A. Minimus he says, "Very like A. Funestus, A. Rhodesiensis, and
A. Superpictus, but from Funestus it can be at once told by the disposition of

* "A Monograph of the Culicidæ of the World,"by F. V. Theobald, Esq., M.A., F.E.S. British
Museum (Natural History), 1901.