33 



The Legs. — The tibise and tarsi present interesting modifications of great 

 value in interpreting relationships. The third tarsal segment may be nearly 

 normal or greatly widened and bilobed; the fourth segment may be distinct, or 

 almost invisibly hidden in the bilobed third segment. The presence of elongate 

 tarsal and tibial hairs is a secondary sexual character in some genera. The 

 shape of the fore tibise and the condition of their spines and serrations are of 

 great importance in the relationships of the larger groups; the individual varia- 

 tions in the tibial serrations, however, are frequently very great. 



Femur - - -X- y ^Trochanter 



^-^ Tarsus 



Fig. 3. — Hylurgops pinitex Fitch; fore leg. Original. 



The scutellum in these insects has the visible portion small, usually with 

 the apex of the process at the level of the elytra, sometimes oblique or depressed 

 and nearly invisible from above. 



The thoracic sterna present important characters, but have been very little 

 used. The condition of the mesosternum is important, particularly in the 

 Hylesinince. The side-pieces of the metathorax are variably exposed, and 

 variably pubescent. The metepimeron is covered by the elytra or partly 

 exposed; the metepisternum almost entirely exposed or nearly completely 

 covered in a few genera. 



THE ELYTRA. 



The elytra are variably striate, punctured, granulate, and pubescent, with 

 serrations in certain genera at the base or on the interspaces of the decHvity. 

 These characters are of the utmost importance in generic and specific arrange- 

 ment. The strial punctures usually bear very minute setse, while the longer 

 hairs are almost invariably from the interstrial punctures. The elytral pubes- 

 cence presents every gradation between slender elongate hairs and very short 

 stout scales; the punctures of the striae and interspaces vary greatly in diameter, 

 shape and depth ; the interspaces may be flat or variably convex with granulations 

 or rugosities. The " suture," the junction of the two elytra along the dorsum, 

 is frequently more or less elevated, particularly behind, by the convexity of the 

 first interspaces, and the first or sutural strise are frequently more deeply im- 

 pressed than the others. The declivity is usually steep, sometimes truncate or 

 concave, or almost absent with the elytra approaching the horizontal behind in a 

 few genera, Eccoptogaster and Leperisinus, (PI. 17, fig. 10). 



THE ABDOMEN. 



The apical tergites and sternites are of some importance, but will not be 

 discussed here. The eighth tergites may be covered or exposed in one or both 

 sexes. The five visible sternites vary considerably in the degree of fusion, 

 relative length, and convexity; rarely they bear teeth or serrations, which may 



36198—3 



