CULICID^. 



369 



ing as scavengers and doing great benefit in clearing swamps 

 of miasms. Occasionally they rise to the surface for air by a 

 jerking movement, inhaling it tkrough the star-like respiratory 

 tube which connects with the tracheae. 



The pupae have club-shaped bodies owing to the greatly en- 

 larged thorax, with two respiratory tubes like those of Corethra, 

 situated on the thorax. They 

 remain near the surface of 

 the water wriggling towards 

 the bottom when disturbed, 

 aided by the two broad 

 swimming caudal leaves. 

 Though active in their hab- 

 its they do not eat. The eggs 

 are laid in a boat-shaped 

 mass, which floats on the surface of the water. About four 

 weeks after hatching the imago appears, so that there are 

 several broods during the summer. The females alone bite, 

 the males not coming into our apartments but spending their 

 lives in the retirement of the swamps and woods. 



This genus abounds in the high Arctic regions as well as in 

 the tropics. Culex pipiens 

 Linn, inhabits Europe, and 

 there are over thirty North 

 American species described in 

 'Various works. 



Figure 274 represents a ver- 

 tical and side view of the head 

 (greatly magnified) of a com- 

 mon species of Culex found in 

 Labrador. The antennas (a) 

 do not reach as far as the tip 

 of the beak, and are supplied 

 at each joint with a thin ver- 

 ticil of hairs (by an oversight 

 partly omitted in the upper fig- 



rig. 274. 



ure). The beak consists of a stout bristle-like labrum (not 

 shown in the figure) ," the bristle-like maxillae (mar, with their 

 rather large three-jointed palpi mp) with the mandibles (m) 

 21 



