112 DIRECT INJURIES CAUSED BY INSECTS. 



that these flies infest, than they immediately desert it and 

 take flight, alighting upon the first living creature that 

 they meet with ; which if it be not a bird they soon quit, 

 but, as it should seem from the above facts, not before 

 they have made a trial how it will suit them as food. 



But of all the insect-tormentors of man, none are so 

 loudly and universally complained of as the species of 

 the genus Culex^ L., whether known by the name of 

 gnats or mosquitos a . Pliny, after Aristotle, distinguishes 

 well between Hymenoptera and Diptera, when he says 

 the former have their sting in their tail, and the latter 

 in their mouth ; and that to the one this weapon is given 

 as the instrument of vengeance, and to the other of avi- 

 dity 5 . But the instrument of avidity in the genus of 

 which I am speaking, is even more terrible than that of 

 vengeance in most insects that are armed with it: like 

 the latter also, as appears from the consequent inflam- 

 mation and tumour, it instills into its wound a poison ; 

 the principal use of which, however, is to render the 

 blood more fluid and fitter for suction. This weapon, 

 which is more complex than the sting of hymenopterous 

 insects, consisting of five pieces besides the exterior 

 sheath, some of which seem simply lancets, while others 

 are barbed like the spicula of a bee's sting, is at once 

 calculated for piercing the flesh and forming a siphon 



* It has been generally supposed by naturalists, that the Mosqui- 

 tos of America belong to the Linnean genus Culex ; but the cele- 

 brated traveller Humboldt asserts that the term Mosquito, signifying 

 a little fly, is applied there to a Simulium, Latr. (Sirnidia t Meig.), and 

 that the Culices, which are equally numerous and annoying, are called 

 Zancudoes, which means long legs. The former, he says, are what the 

 French call Moustiques, and the latter Maringouins. Personal Nar- 

 rative, E. T. v. 93. 



b Plin. Hist. Nal. I. xi. c. 28. Aristot. Hist. Animal. I. i. c. 5. 



