PHLEB0T0MU8 FLIES 



467 



The phlebotomus flies (Fig. 212D) are small dull-colored in- 

 sects, usually yellowish or buff, slender in build, with hairy 

 body and very long and lanky legs. The hairy-veined wings 

 are narrow, somewhat the shape of mosquito wings, and are held 

 erect over the body when the insect is in repose. The wings are 

 quite remarkable for the inconspicuousness of the crossveins which 

 gives them the appearance of having nine or ten nearly parallel 

 longitudinal veins. The antennse are long, consisting of a series 

 of beadlike segments with whorls of hairs at the joints. The 



Fig. 212. Life history of piilebotomus fly, Phlebotomus papaiasii; A, egg; 

 B, larva; C, pupa; D, adult. A, X 80; B, C and D, X 8. (After Newstead.) 



relatively long proboscis is made up in practically the same way 

 as is that of a mosquito (see p. 426), except that the needle-like 

 organs project beyond the tip of the sheath made for them by 

 the labium or lower lip. These insects are usually less than 

 one-fifth of an inch in length and often not over one-eighth of 

 an inch; they can easily crawl through the meshes of an ordinary 

 mosquito net, and are therefore hard to avoid. Their bites are 

 very annoying and cause an amount of irritation which seems 

 quite out of proportion to the size of the insects. In most cases 

 it is only the female which sucks blood, but in some species the 



