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American Midland Naturalist Monograph No. 3 



terminal hdir (10), and the dorsal and ventral sabres (Fig. 19B). Characters of 

 the following paired head hairs are generally referred to in specific descriptions : 

 Inner clypeals (2); outer clypeals (3); postclypeals (4); the frontal hairs, 

 which are made up of the inner frontals (5), middle frontals (6), and the 

 outer frontals (7); sutural hairs (8); trans-sutural hairs (9); basal hairs (12); 

 sub-basal hairs (13); supraorbital hairs (14); and the infraorbital hairs (15). 

 The infra-orbitals are not seen in a dorsal view. 



THORAX. (Fig. 20). — Those hairs of the thorax which may be used in 

 classifying the Anophelines are the inner, middle and outer submedian pro- 

 thoracic hairs (1-3), sometimes referred to as the shoulder hairs; the lateral 

 hairs (4-8); the groups of four hairs known as the pleural hairs (9-12) on the 

 ventral surface of the pro-, meso-, and metathorax (Fig. 20B, C, D) ; and the 

 ventral submedian hair (13). Most of the larger hairs are pinnately branched, 

 a feature which is peculiar to Anophelines. Hair 1 of the metathorax is, in 

 some species of Anopheles, a thoracic palmate hair similar to the palmate hair 

 (1) on the abdominal segments. Hair 1 is similarly developed on the meso- 



onterior plate 



splrocle 



— Vloferol flop 



main tergal plote 



\ , median plate 



B 



dorsal brush 



Fig. 22. Abdomen of Anopheles larva. A, Spiracular apparatus (dorsal view). B, 

 Terminal segments VII to IX (lateral view). Segment VII : (0-8), same as for segments 

 I to VI in Fig. 21. Segment VIII : (4 and 5), hairs of lateral flap; (6), pecten hair; 

 (7), subpecten hair; (8), small lateral hair; (9), ventro-lateral posterior hair; (10), 

 small ventro-lateral hair; (13), ventral submedian hair. 



