26 



MOSQ UITO ERA DICA TION 



Adult Anopheles also may be identified by their peculiar pos- 

 ture while resting or biting. On a vertical wall, the head, thorax 



Fig. 18. — Head of Anophe- 

 les, male. (After U. S. Pub- 

 lic Health Service.) 



Fig. 19. — Head of Anophe- 

 les, female. {After U. S. 

 Public Health Service.) 



and abdomen form one straight line, pointing downward at an 

 angle of about 60 degrees from the horizontal; other common 



1 z 3 



Fig. 20. — Resting posture of mosquitoes. (After Sambon.) 1 and 2, Anopheles; 



3, Culex pipiens. 



mosquitoes sit humped up, both head and abdomen being lower 

 than the thorax. 



Fig. 21. — Ova of Anopheles. Fig. 22. — Culex egg raft. (After 



(After U. S. Public Health U. S. Public Health Service.) 



Service.) 



Adult Anopheles also may be distinguished from other common 

 mosquitoes by their actions. They seldom bite in the day-time 

 and rarely bite a person moving about; the Culex, 

 on the other hand, bites at all times. The 

 Anopheles does not hum so loudly as other com- 

 mon mosquitoes. 



Fig. 23. — Greatly enlarg- 

 ed view of a Culex egg. 

 (After U. S. Public Health 

 Service.) 



Fig. 24/ — Greatly enlarged 

 view of an Anopheles maculi- 

 pennis egg. (After U. S. Pub- 

 lic Health Service.) 



