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       The median hairs arise close together near the middle line and project
forward in front of the head. They are not difficult to see with a ½ or ¼ inch
objective. A very important difference between the larvæ of different species
depends upon the fact that the characters of these external and median frontal
hairs differ in different species.

       Thus in some species both the external and median hairs are simple and
entirely unbranched (see figure 7, Larva of A. Rossii), in other species both pairs
of hairs are slightly branched (e.g., A. Superpictus, Grassi), in others the
median hairs are slightly branched or frayed, while the external are very much
branched ("like a small tree," Grassi, e.g. A. Fuliginosus), and again the
median may be simple or slightly branched and the external undergo dicho-
tomous branching so that it forms a very prominent and distinct "cocade"
(A. Nigerrimus, A. Barbirostris).

       Further details regarding these hairs are given under the descriptions of
the different anopheles of India.

[NLS note: a graphic appears here - see image of 75022450.tif]

Fig.7.—The larval characters of A. Rossii.