PHYSIOLOGY OF INSECTS. 109 



of some insects are flabellate throughout, others 

 have only the apical portion flabellate. 



372. Ciliate antennae (antennae fimbriatce) are 

 those which, in primitive structure, are setaceous ; 

 but each joint is furnished on each side with a 

 single hair. 



373. Elbowed, kneed, or broken antennae (an- 

 tennae fractce), are those which have one joint, 

 usually the second from the base, very long, and 

 the remaining joints attached to it at a right 

 angle. 



374. Pilose antennae (antennae pilosae) are not 

 of any peculiar structure, but are covered entirely 

 with a soft down. 



375. Setose antennae (antennae setosae) are not 

 of any peculiar structure, but are furnished 

 throughout with irregular harsh bristly hair. 



376. Plumose antennae (antennae plumosae) are, 

 in primitive form, setaceous, but are furnished 

 with long downy hairs, which give them the ap- 

 pearance of a feather. 



377- Ramose antennas (antennae ramosae} are 

 generally of setaceous or moniliform structure, 

 but differ in having several joints near the base, 

 produced into long branches, sometimes nearly 

 equalling the antenna itself in length. 



378. Bifurcate antennae (antennae bifurcae) are 

 generally composed of three joints, of which the 

 apical one is very long, bent double, and attached 

 at its centre to the second joint. 



