DIRECT INJURIES CAUSED BY INSECTS. 109 



tear you will be disappointed, since I have many more, 

 and some tremendous ones, to enumerate : but as a small 

 compensation for such a detail of evils and injuries to 

 which our species is exposed from foes seemingly so in- 

 significant, and of acts of rebellion of the vilest and most 

 despised of our subjects against our boasted supremacy, 

 the objects to which I shall next call your attention are 

 not, like most of our apterous enemies, calculated to ex- 

 cite disgust and nausea when we see them or speak of 

 them ; nor do they usually steal upon us during the si- 

 lent hours of repose, (though I must except here the gnat 

 or mosquito,) but are many of them very beautiful, and 

 boldly make their attack upon us in open day, when we 

 are best able to defend ourselves. Borne on rapid wings, 

 wherever they find us, they endeavour to lay us under 

 contribution, and the tribute they exact is our blood. 

 Wonderful and various are the weapons that enable 

 them to enforce their demand. What would you think 

 of any large animal that should come to attack you with 

 a tremendous apparatus of knives and lancets issuing 

 from its mouth ? Yet such are the instruments by means 

 of which the fire-eyed and blood-thirsty horse-fly ( Td- 

 banus, L.) makes an incision in your flesh ; and then, 

 forming a siphon of them, often carries off many drops 

 of your blood a . The pain they inflict, when they open 

 a vein, is, usually very acute. A fly of this kind not 

 only occasioned Mr. Sheppard considerable pain by its 

 bite, but also produced swelling and blackness round 

 one eye ; and the flesh of his cheek and chin was so en- 

 larged from it as to hang down. And Mr. W. S. Mac- 

 Leay thus describes to me the annoyance he suffered 



* One took eight drops from Reaumur, iv. 230. PLATE VII. FIG. 5. 



