THE ANTENNAE OF A BEETLE. 



13 



(k) Capitate or head-like, when the outer joints are suddenly 

 larger, forming a compact rounded elub. 



15, lamellate; 16, irregular, (After LeConte and Horn.) 



(I) Lamellate, a form of clavate antennae in which the outer 

 joints are leaf-like plates which may be brought closely in contact, 

 thus forming a transverse or rarely rounded club, supported at one 

 side by the stem of the antennae. 



The antenna? are said to be geniculate or elbowed when the sec- 

 ond joint is attached to the first in such a way as to make an obtuse 

 angle, the joints after the second following in the same line as the 

 latter. In this form the first or basal joint is usually much longer 

 and is called the scape. When the antenna is both geniculate and 

 capitate, the joints between the scape and club are together called 

 the fumcle. 



The antenna! grooves are concave, usually elongate and narrow 

 areas on the under side of the head or presternum, in which the an- 

 tenna? are concealed or placed in repose. When on the under side 

 of the head they usually are close to the eye and converge on the 

 gula. 



The antenna? of beetles are supposed to be primarily organs of 

 smell, but also bear nerves of touch. In a number of species they 

 are put to other uses ; it being said that certain Cerambyeids in 

 walking along a slender twig use them as a rope-walker does his 

 balancing pole ; while those of certain aquatic forms are used in 

 connection with respiration, and those of the male Meloe as clasping 

 organs. 



