THE MOSQUITO 49 



proboscis is fruitless, and we have watched 

 a mosquito attempt four times to pierce the 

 skin before it drew blood. If undisturbed 

 during the meal the suctorial repast may last 

 some two or three and a half minutes. So 

 greedy at times is the mosquito that she 

 resembles Baron Munchausen's horse after the 

 adventure with the portcullis — what is flow- 

 ing in at one end is flowing out at the other. 

 In fact, as Dr. Johnson said of the boys at 

 a school ' where discipline was maintained 

 without recourse to corporal punishment,' 

 ' But, sir, what they gain at one end they 

 lose at the other ! ' After the process of biting, 

 of sinking-in of the piercing needles, is com- 

 plete, the proboscis is withdrawn, and to do 

 this the mosquito braces herself on her legs 

 and raises her body. 



Another curious feature about the head 

 of Anopheles is that it is pierced by two chiti- 

 nous, symmetrical tunnels — tubes which are 

 open at each end with trumpet-shaped orifices. 

 The use of these is probably to act as a stay or 

 strut to strengthen the chitinous exoskeleton of 

 the head ; but these queer galleries or tubes also 

 to some extent act as attachments for muscles. 



The antennae vary very much in the two 

 sexes. In the female there are fifteen seg- 

 ments, each bearing a ring of hairs, but of 

 small and disproportionate size, whereas in 



