PARASITES OF ANIMALS. 



cally developed. The jaws are used for biting and cutting the 

 materials used in constructing their nests ; the maxillae are 

 used in manipulating and arranging ; the tongue is used for 

 lapping up honey and otlier liquid food. The larvae are gen- 

 erally soft, footless, and white, but those of the saw flies re- 

 semble caterpillars, and have numerous abdominal legs. 



II. Biptera (two-winged). Insects belonging to this order 

 have but one pair of wings. The three regions of the body 

 are very distinct. The common house-fly, meat-flies, mos- 

 quito, Hessian-fly, wheat-midge, onion-fly (figure 9), bot-fly, 

 Fig. 9. horse-fly, and the fleas 



are examples. The 

 mouth organs corres- 

 pond in number with 

 those of the Hymen- 

 optera, but the mandi- 

 bles and maxillce are 

 usually formed like 

 long sharp lancets, as 

 in the horse-fly (fig. 

 10), or have the shape of slender and 

 sharp piercing organs, as in the mosquito. 

 The labium and tongue together generally 

 form a long proboscis, often with the 

 tongue curiously bilobed and expanded at 

 the end as in the horse-fly and house-fly. 

 The sharp mandibles and maxillae are used 

 to penetrate the "fekin of animals, or the 

 bark of plants, and rind of fruits, and the fleshy tongue is 

 used to suck up the blood or other liquid food. Tlie larvae 



eyes ; h, clypeus ; c, the three simple eyes or ocelli ; d, the antennae ; e, labrum or 

 upper lip ; f, mandibles ; h, maxillary palpi, borne upon the base of the maxillse 

 i, which ai'e slender and hairy ; j, labial palpi ; k, ligula or tongue ; /, palpifer ; 

 m, paraglossae or lateral lobes of the ligula. Erom Packard's Guide, after New - 

 port. 



Figure 9. — Onion-fly {Anthomyia ceparuni), considerably enlarged, with larvae, 

 a and b. From Packard's Guide. 



Figure 10. — Head of Green-head fly or Horse-fly ( Tahamis lineola Fabr.), much 

 enlarged ; a, antennte ; m, mandibles ; mx, maxillse ; mp, the large, two-jointed 

 maxillary palpi ; I, the ligula or tongue ; lb, the labrum. From Packard's Guide. 



Fig. 10. 



