12 OOLEOPTERA OF INDIANA. 



which the antennas end in an abrupt club the pores are confined to 

 its surface; in most cases, however, they are generally scattered 

 over all except the basal joints. 



The principal forms of antennas are as follows : 



(a) Filiform or thread-like, where the joints are cylindrical 

 and the outer ones not or scarcely enlarged. 



(6) Setaceous or bristle-like, where the joints are gradually 

 more slender to the tip. 



(c) Capillary or hair-like, where the joints are long, slender 

 and very loosely united. 



' 



Fig. 3. Serrate antennae and modifications: 1, serrate; 2, pectinate; 3, bipectinate; 4, flabellate; 

 5, plumose; G, 7, 8, irregularly serrate. (After LeC'onte and Horn.) 



(d) Moniliform or bead-like, when the joints are of nearly 

 uniform size and rounded, thus resembling a string of beads. 



(e) Serrate or saw-like, when the joints are triangular and 

 compressed, presenting therefore a saw-tooth-like outline on the 

 front margin. 



(/) Pectinate or comb-like, when the joints are short, with 

 their front angles much prolonged. 



(g] Bipectinate, when each joint has a comb-like tooth on c-nr-h 

 side. 



(/O Flabellate or fan-like, when the prolongations from rl < j 

 joints are very long compared with the antenna?, and fold together 

 like a fan. 



(?) Plumose or feather-like, when the prolongations are long 

 slender and flexible. 



(j) Clavate or club-like, where the outer joints are more or 

 less enlarged, but not triangular or leaf -like. This is among beet it. 

 the most common form of antennas, and it grades gradually 

 most of the other types. 



