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Where would you expect to find the Larvae of Mosquitoes ? 



Along the margins of streams, swift or sluggish ; in 

 almost every pond, pool and ditch ; in puddles clean or 

 foul, and in standing water (e.g., about houses, in holes 

 of trees), no matter how slight the quantity may be. Wood- 

 land ditches full of fallen leaves, ponds, and rainwater 

 barrels are the favourite breeding places of Culex pipiens. 



The larvae of the species of Stegomyia are generally 

 found in pots, tins, 'or barrels containing water. 



Swampy pools, irrigation channels, and the weedy 

 margins of slow-flowing streams are the principal resorts 

 of many Anopheline species. 



Pyretophorus costalis, the commonest West African 

 Anopheline, breeds in roadside puddles, and in barrels 

 and pots about the native dwellings. In tropical countries 

 during the rainy season the numbers of mosquitoes are 

 greatly increased, and the subsequent result is epidemics 

 of malaria. 



Describe the External Features of a Mosquito, e.g., Anopheles 

 maculipennis (the Spotted Gnat). 



The slender body is about a quarter of an inch long. 

 The head has two prominent compound eyes, two long 

 plumose antennae composed of fifteen joints, and a long 

 piercing proboscis. The thorax, grayish brown and hairy, 

 consists of three fused segments and bears three pairs of 

 long and slender legs, a pair of wings, and two minute 

 halteres or balancers. When expanded, the membraneous 

 wings measure nearly half an inch ; each has four charac- 

 teristic spots, and towards the apex there are two bifurcated 

 veins separated by a simple vein. The abdomen has eight 

 segments ; there are fine hairs and scales on the body, 

 and scales on the wing veins. In repose the hindmost legs 

 are held raised, a habit diagnostic of mosquitoes. 



Write an Account of the Mouth-parts, Mode of Feeding, and 



Alimentary Organs of a Mosquito. 



The mouth-parts are lengthened and together form a 

 piercing proboscis which has the following parts : The 



