32 
A Monograph of Culicidae. 
flattened, and has a row of feathered bristles on its front ed"e ; 
in th.e middle above the pleurae is formed another row of such 
bristles, and still further back three much longer feathered 
bristles on each side. 
“ The abdomen is rounded, and, like the preceding, of nine 
segments, which decrease in breadth backwards, but increase 
somewhat in length, the first three segments have long feathered 
bristles ; those on the other somites are smaller ; the eighth 
joint bears on its upper surface two small simply formed spir¬ 
acles, each of which can be drawn back under a fold of skin 
at will ; the ninth joint bears on its under side a row of lono- 
feathered bristles which form a swimming fan; there are four 
anal papillae rather slender and pointed ; no anal hooks are 
present.” 
Grassi has pointed out that the two branched hairs found 
at the corners of the dorsal end of the head, and the two 
simple or slightly plumose hairs near the middle, are of specific 
importance, and by them he can detect the larvae of A. maculi¬ 
pennis, A. bifurcatus, A. superpictus, and A. pseudopictus 
(Plate IV. Grassi). 
The mouth of Anopheles larva is made of a pair of mandibles, 
a pair of maxillae, and a small lower lip. The mandibles are one- 
jointed hard structures, with three curved stout bristles on one 
side near the apex, five teeth at the apex, and two brushes of 
fine hairs. The maxillae are provided with a distinct palp 
ending in several spines and a jflate, and bear on the side a 
feathered bristle. Between the large basal piece of the two 
maxillae lies a small plate, the lower lip. The maxillae have 
many fine hairs. ISluttall and Shipley state that the palp ends 
in three spines and a plate ; the specimens I examined had five 
spines, and may thus have been the larva of A. bifurcatus. 
The thorax is much wider than the head in the adult, but in 
young larvae the head is broader than the following segments. 
The feathered bristles on the thorax seem to vary in different 
species. In A. maculipennis there are three feathered bristles on 
each side in front, three larger ones on each side behind, and four 
small median ones in two pairs on the dorsum, as well as single 
bristles laterally. In the figure (p. 31) the bristles are seen to 
be differently arranged. Nuttall and Shipley figure a small 
bifid process on each side of the thorax in A. maculipennis, which 
I cannot detect in the larva here figured. 
The abdomen consists of nine segments. The first two 
