3 i4 EASTERN ETHIOPIA xxv 



life. Mosquitoes abound in all climates : they swarm 

 in tropical and subtropical countries ; and are found in 

 Arctic regions. 



The life-history of the Mosquito is briefly this : 

 The eggs are laid by the female in water, on damp 

 mud, or on leaves. The incubation period occupies a 

 few days, and the larva emerges and lives in the water. 

 Any collection of water is useful for this purpose, such 

 as lakes, ponds, rivers, pools or puddles, cisterns, rain- 

 water tanks, calabashes, flower-stands, or gallipots, the 

 fluid in the pitchers of the Nepenthes plant, and in the 

 deep concavities of the leaves of the pine-apple. 



The larvae, popularly known as wrigglers, live a short 

 time and then pass into the pupa stage ; the pupae 

 constantly come to the surface of the water to breathe. 

 The duration of the pupal life varies from two to twelve 

 days. When the pupae are ready to hatch they rise to 

 the surface of the water and as they straighten out the 

 pupa-case splits over the thorax. The mosquito then 

 uses the case as a raft whilst its wings dry and then 

 flies away. The majority of mosquitoes hatch out in 

 the early morning or at midday. 



The adult mosquito prefers night for feeding : during 

 the day it hides away in shrubs, bushes, and in the 

 corners of huts, tents, and houses. For food, certain 

 species take vertebrate blood ; this they obtain by means 

 of an efficient organ known as the proboscis. The females 

 alone have the blood -sucking habit, the males feeding on 

 plants. 



Mosquitoes have always been regarded as pests in all 

 warm countries. In districts where they abound the 

 inhabitants have been accustomed to exclude them from 

 the dwelling apartments, and especially from the sleep- 

 ing-rooms, by means of mosquito curtains made of a 

 thin material which cannot exclude air and light, yet is 

 sufficiently strong to prevent the ingress of these trouble- 

 some insects. These measures were taken, not because 

 the mosquitoes were known to be winged-vehicles of 



