FIELD BOOK OF INSECTS. 



As far as we are concerned, Trox (Plate LXXX) is the 

 only genus of Trogini. Its species are oblong, convex, 

 dirty-looking, brown beetles, which occur under or about 

 carrion, old hides, or feathers. The surface is usually 

 roughly sculptured and covered with a crust of earth which 

 is difficult to remove. Adults stridulate by rubbing the 

 abdomen against the elytra, special areas being roughened 

 "for this purpose." 



Melolonthinae 



Here belong the June Bugs or Cockchafers. The adults 

 are often very abundant about lights and feed chiefly on 

 leaves. The abdominal spiracles are placed almost in a 

 line but not more than the front three spiracles are on the 

 membrane connecting the dorsal and ventral parts of the 

 abdomen. The larvae live in the ground and feed chiefly 

 on roots. Our principal genera may be separated as 

 follows: 



1. Middle and hind tibiae with only one spur, this some- 

 times obsolete; hind tarsi with a single claw Hoplia. 



Middle and hind tibiae with two spurs; all tarsi with 

 two equal claws 2. 



2. Form elongate, slender; colors metallic green or 

 bronzed or dull yellow 3. 



Form robust, heavy; color brownish, sometimes 

 iridescent 4. 



3. Elytra pubescent, not densely scaly; claws capable 

 of being folded along the last joint of tarsi. . .Dichelonycka. 



Elytra densely covered with elongate, yellowish 

 scales ; tarsal claws not as above Macrodactylus. 



4. Five ventral, abdominal segments; elytra either 

 uniformly and rather finely punctured or with punctured 

 striae Diplotaxis. 



Six ventral, abdominal segments 5. 



5. Less than .5 in. long; elytra with indistinct but regular 

 grooves Serica. 



Usually more than .5 in. long; most of the elytra 

 without striae or grooves Phyllophaga. 



330 



