14 Guide to Insects and Ticks 



in many species conspicuous white transverse bands at the base 

 of each segment ; in anophelines the abdomen is without distinct 

 scales, and hence without well-defined markings. 



In the lower part of the South side of the case are displayed a 

 series of models, enlarged 28 diameters, like those of the adult 

 insects, showing the appearance of the eggs, the larvae and the 

 pupae of O//rr and AnopJu-les. The black threads stretched 

 horizontally represent the surface of the water. The eggs of 

 mosquitoes float upon the surface, and the larvae and pupae move 

 about in the water, breathing by means of their air-tubes, which 

 now and again are caused to project very slightly above the 

 surface. The eggs of Culex are massed into a raft composed 

 of two or three hundred eggs with their more pointed ends 

 directed upwards. The eggs of Anopheles float singly or in 

 small groups easily scattered by the wind, and are disposed on 

 their sides instead of standing erect upon the water. Each egg 

 has a pair of small air spaces, as shown in the upper model ( x 65) 

 at the right hand end of the series, above the group of eggs 

 (X38). 



The characteristic attitude of the larva of the culicine mosquito 

 is one in which the head is downmost, the body slightly inclined 

 to the vertical, and the extremity of the air tube at the hind end 

 of the body just touching the surface of the water. The larva of 

 the anopheline mosquito rests horizontally just below the surface 

 of the water ; the air-tube at the hind end of the body is very short, 

 and just level with the surface. When feeding, the larva twists 

 its head half-way round, and laps the surface of the water for 

 minute vegetable organisms. Both culicine and anopheline larvae 

 when alarmed strike down into the water with a rapid jerking 

 movement. 



The pupae of the culicine and anopheline mosquitoes do not 

 differ greatly. In each case the pupa rests with the two horn-like 

 air-tubes on the thorax at the surface of the water, but it can swim 

 rapidly by a jerking movement of the abdomen, which is provided 

 at its extremity with two transparent paddle-like organs. 



In the lower part of the North side of the case are enlarged 

 drawings of the mouth-parts of the two species of gnat or mosquito 

 illustialrd, the culicine, r//A-.r jiij>icns, and llio iiiiophelinc, 

 .\nnjilirli-fi maculipennis. TIM- proboscis of mosquitoes consists of 

 si long, channelled lahium and six piercing instruments contained 



