MANUAL OF NATURAL HISTORY. 255 



11. FAMILY. Chameleon-Flies (Stratiomidas). An- 



tennae of six or seven joints, usually end- 

 ing in a style or seta ; organs of mouth ru- 

 dimentary scutellum often spined ; body 

 broad, depressed ; wings incumbent when at 

 rest ; terminal veins very slender. Found 

 upon flowers in watery situations. 



12. FAMILY. Tree-Flies (Xylophagidae). Antennas 



10-jointed, without any seta, the last joints 

 forming a cylindric mass; scutellam unarm- 

 ed ; body narrow, cylindrical ; wings parallel, 

 incumbent or laid upon abdomen in repose. 

 On trees. 



13. FAMILY. Breeze-Flies (Tabanidse). Antennas 



with third joint large, remaining joints 3 7, 

 closely united, tapering to the tip ; proboscis 

 exserted, enclosing lancets, and ending in two 

 fleshy lobes ; eyes large ; scutellum large, 

 elevated ; abdomen triangular, depressed ; 

 wings extended horizontally, winglets large 

 Pierce the skin and suck the blood of man 

 and the lower animals. 



14). FAMILY. Humming-Bird Flies (Bombyliidaa). 

 Antennas close together at base, often with a 

 short terminal style ; proboscis long, por- 

 rected in front of head ; thorax much ele- 

 vated ; body short, thick, often clothed with 

 hairs ; wings horizontal, winglets small ; legs 

 very long and slender. Fly with great rapi- 

 dity; hover over flowers without settling ; 

 make a humming noise with their wings. 



