External Structure of a Mosquito (Scales). 13 
shape and occur as a layer beneath the longer ones ; the stalk 
of these fringe-scales often reaches a considerable- length. 
“Border scales” (Fig. 7, II. bs.) are small, and resemble the 
“ flat scales ” of the head and body but are smaller and narrower ; 
in some cases “ border scales ” are very narrow and very small, in 
others ( Panoplites , &c.) they may be spatulate or asymmetrically 
broadened as those on the veins in that genus. 
The scales of the wings are usually brown, yellow, or white, 
but in Megarhinus they may be azure blue or green, whilst in 
Mucidus they are parti-coloured—half dark and half white—a 
character seen in no other genus ; in certain Anopheles 
(A . Grabhamii) they are jet black. The fringe-scales are often 
all one colour, but they may, as in Mucidus and Anopheles , be 
alternately dark and pale in definite tracts; in a few Culices 
the fringe appears white in some lights, dark in others ; those 
on the basal lobes of the wing vary in form and are often dark. 
(5.) Scales Of the leg’s. —In nearly all members of the 
family the legs are clothed evenly with flat scales, which form a 
complete covering ; these leg scales often exhibit marked metallic 
hues in certain lights and sometimes form dense tufts. In a few 
cases the leg scales become much narrowed, and form hair-like 
scales which may occur in tufts as in Sabethes and Eretmapodites. 
In Mucidus and Psorophora the leg scales become elongated in 
places and stand away from the surface of the legs ; in Aedeomyia 
they are still further modified, becoming elongated, with a thin 
stem and expanded apex. 
(6.) Scales on the proboscis, palpi and antennae.— 
The scales on the proboscis are found only on the sheath, and 
are usually small flat scales, but in some Anopheles (A. Sinensis, 
&c.), they stand at an angle to the surface, in others the scales 
are absent. The palpi in some species, as Culex (Janthinosomd) 
musicus , Say, may be densely scaled so that the joints are not 
visible, or the scales may be closely applied to their stirface or 
even absent. The basal joint and first two or three of the 
following joints of the antennae may also be scaled; in Mega¬ 
rhinus the second joint is densely covered, whilst in Culex , &c., 
only a few scales exist on the feelers. 
Coloration produced by scales. —The squamae in this 
family, like those of the Lepidoptera, account for the colours 
of the insect. 
