804 AN INTRODUCTION TO ENTOMOLOGY 



Family CULICID^ 

 The Mosquitoes 



The form of mosquitoes is so well known that it would be un- 

 necessary to characterize the Culicida) were it not that there are 

 certain mosquito-like insects that are liable to be mistaken for mem- 

 bers of this family. 



The mosquitoes are small flies, with the ab- 

 domen long and slender, the wings narrow, the 

 antennaj pkunose in the males, (Fig. 1018), and 

 usually with a long, slender, but firm proboscis. 

 The thorax lacks the transverse V-shaped suture 

 characteristic of the crane-flies; and vein M of the 

 wings is only two-branched. But the most dis- 

 tinctive feature of mosquitoes is the fringe of 

 scale-like setae on the margin of the wings and also 

 inmost cases on each of the wing-veins (Fig. 1 01 9). 



The eyes are large, occupying a large part of 

 the surface of the head. The ocelli are wanting. 

 The antenna} are composed of fifteen segments, of 

 which the first segment, the scape, is concealed by the large globular 

 pedicel (Fig. 173. p. 153) and has been over-looked by many describ- 

 ers of mosquitoes. The pedicel contains the Johnston's organ de- 

 scribed on pages 152 to 154. The form of the mouth-parts differs in 

 the two subfamilies; those of Anopheles are represented by Figure 



Fig. 1018. — Antennas 

 of mosquitoes, m, 

 male; /, female. 



Fig. 1019. — Wing of a mosquito. 



990 on page 775 ; in the Corethrinas they are short and not adapted for 

 piercing. 



The larvae of mosquitoes are all aquatic. They are well known 

 and are commonly called "wigglers," a name suggested by their 

 wriggling motion as they swim through the water. They vary in 

 details of structure but the larva of Culex will serve to illustrate the 

 general form of the body (Fig. 1020). The head and thorax are 

 large and the abdomen is slender. The next to the last abdominal 

 segment, the eighth, bears a breathing-tube; and when the larva is at 

 rest it hangs head downward in the water, with the opening of this 



