26 THE CLASS OF INSECTS. 



The Antennce (Figs. 35, 3G) are inserted usuallj- in tlie adult 

 insect between, or in front of the eyes, though normally the 

 antennar}^ is posterior to the ophthalmic ring. 

 It is normall}' a long, filiform, slender, mauy- 

 jointed appendage, undergoing gi'eat changes 

 in form. AVhen it is higlil}- specialized, as in 

 Coleoptera and Hjnnenoptera, it is divided 

 into three parts, the basal or scape, the middle :>^ 

 or pedicel, and the terminal part or Jiagellum, ^'^- ^• 

 Fig. 35. or clavola, which usually comprises the gi-eater part of 

 the antenna. 



It is believed b}^ some that the sense of hearing is lodged 

 in the antennse, though Siebold has discovered an auditory 

 apparatus situated at the base of the abdomen of some, and 

 in the fore-legs of other species of Grasshoppers. 



Mr. J. B. Hicks has made the latest studies on the auditoiy 

 apparatus. According to him "it consists first of a cell, sac, 

 or cavity filled wdth fluid, closed in from the air b}' a mem- 

 brane analogous to that which closes the foramen ovale in the 

 higher animals ; second, that this membrane is, for the most 

 part, thin and delicate, but often projects above the surface, in 

 either a hemispherical, conical, or canoe-shaped, or even hair- 

 like form, or variously marked ; thirdlj', that the antennal nerve 

 gives off branches which come in contact Avith the inner wall of 

 the sacs ; but Avhether the nerve enters, or, as is most probable, 

 ends in the small internally projecting papilla which I have 

 shown to exist in many of these sacs, it is ver}' difficult to sa}'. 

 The principal part of the nerve proceeds to these organs, the 

 remaining portion passing to the muscles, and to the roots of 

 the hairs, at least to those of the larger sort." On the other 

 hand, Lefeb\Te, Leydig, and Gerstaecker regard this so-called 

 "auditory apparatus" as an organ of smell. 



The antennae have also the sense of touch, as may readilj' be 

 observed in Ants, Bees, and the Grasshopper and Cocki-oach. 

 "The Honej^-bee, when constructing its cells, ascertains their 

 proper dii-ection and size by means of the extremities of these 



Fig. 35. Filiform autenna of AmpMzoa. — From Horn. 



Fig. 36. A, lamellate auteuna of a Lamellicorn Beetle; B, antenna of a Fly, 

 with the bristle thrown ofl' from the tenniual joint; C, bristle-like autenna of a 

 Dragon-fly, Libellula. — From Sanborn, 



