34 Mosquitoes 



" similar impertinent diptera," which are attracted 

 by the eye water. All these small flies, as well as 

 other larger ones, are on the way to blood-sucking. 

 The Culicids, at first suckers of plant juices, learned 

 the taste of animal blood by means of the bloody 

 serum from wounds, and the males content them- 

 selves with this, but the females formed the habit of 

 puncturing the skin in order to obtain the desired 

 liquid. Having a better biting equipment than the 

 males and utilising the blood as nutriment for the 

 forming of eggs, the taste easily became an indis- 

 pensable necessity — another example of the fitting 

 of the body of the female first of all to the necessities 

 of reproduction. Thus the blood-sucking habit, 

 accidentally acquired, becomes an essential factor in 

 the maturing of the sexual products of the female ; 

 to-day these insects demand blood as a necessity for 

 the propagation of their species. 



Referring particularly to C. fatigans as a basis for 

 observation, he states that fertilization seems to 

 stimulate the desire for blood, and, as far as known, 

 it is principally the fecund female which bites. She 

 selects a place near a blood-vessel. " Untroubled, 

 lifting the hind legs, rubbing and moving them back 

 and forth, in visible satisfaction, she fills herself full, 

 literally to the point of intoxication," when she 

 "finally flutters drunkenly to the wall," so full that 

 she is " transformed into a deformed tube " so trans- 

 parent that the red fluid may be seen through the 

 body wall. There she sits digesting quietly. In 

 about twenty-four hours there is a visible diminu- 

 tion of the abdominal contents, marked by repeated 



