58 



TEXT-BOOK OF ENTOMOLOGY 



while in Otiocerus, two long processes arise from the base, giving it 

 a trificl shape. In dragon-flies and cicadae, they are minute and 

 hair-like, though jointed, while in the larvae of many metabolous 



FIG. 43. Different forms of antennas of beetles : 1, serrate ; 2, pectinate ; 3, capitate (and also 

 geniculate) ; 4-7. clavate ; 8, 9, lamellate ; 10, serrate (Dorcatoma) ; 11, Irregular (Gyrinus) ; 12. two- 



join te<l antenna of Aili'unex cifi'iix. After LeConte. a, first joint of tiagellum of antenna of Trocten 

 xilnirum ; b, of T. >li rinntoriux. After Kolbe. 



insects they are reduced to minute three-jointed tubercles. In 

 aquatic beetles, bugs, etc., the antennae are short, and often, when 

 at rest, bent close to the body, as long antennae would impede 

 their progress. 



While usually more or less sensorial in function, 

 Graber states that the longicorn beetles in walking 

 along a slender twig use their antennae as a rope- 

 dancer does his balancing pole. 



Recent examination of the sense-organs in the 

 antennae of an ant, 

 wasp, or bee enables 

 us, he says, to realize 

 what wonderful or- 

 gans the antennae are. 

 In such insects we 

 have a rod-like tube 

 which can be folded 

 up or extended out 



FIG. 44. Tripec- . 



antenna ..i an into space, containing 



Australian moth. 



the antenna! nerve, 



FIG. 45. Antenna uf TnJarocera iii- 

 tix, J 1 . After Williston. 



which arises din-rtly from the brain and sends a branch to each of 

 the thousands of olfactory pits or pegs which stud its surface. The 

 antenna is thus a wonderfully complex organ, and the insect must 



