202 COLEOPTERA OF NORTH AMERICA. 



Prothorax with the side pieces not separate; coxal cavities 

 large, transverse; protlioracic spiracle usually visible; pro- 

 sternum very short. 



Mesosternuin triangular, not excavated ; side pieces large, 

 attaining the coxa3. 



Metasternum with side pieces large: epimera visible. 



Elytra never embracing strongly the sides of the abdomen, 

 sometimes short, sometimes (in the female of foreign genera) 

 entirel}^ wanting. 



Abdomen with seven or eight free ventral segments. 



Anterior coxte contiguous, conical, with large trochantin; 

 middle cox^ oblique, contiguous (except in Lycini), conical, 

 with or without trochantin; posterior coxas transverse, 

 prominent, internally forming a conical protuberance. 



Legs slender, or compressed, long or moderate; trochanter 

 in the axis of the thigh; tibiae with short or indistinct ter- 

 minal spurs; tarsi 5-jointed, not lobed beneath, uniformly 

 pubescent in the first, spongy pubescent in the second and 

 third sub-family, fourth joint more or less bilobed; claws 

 variable in form. 



Insects of moderate, or small size, of elongate form, and soft 

 consistence, found on plants. Many of the species of the second 

 tribe of the first sub-family possess the remarkable power of 

 emitting light, and are hence called fireflies. 



The species may be naturally divided into three sub-families of 

 equal value, as follows : — 



Middle cox?e contiguous ; epipleurfe distinct. 2. 



Middle coxse distant ; epiiileurse wanting. Lycini. 



2. Episterna of metathorax sinuate on inner side ; epipleurje usually wide 



at the base. Lampyrin^. 



Episterna of metathorax not sinuate on inner side ; epipleurae narrow 

 at the base. Telephokin^. 



Sub-Family I.— LYCINI. 



The species of this sub-family are diurnal in habits and are 

 found on the leaves. of plants, where they seek their insect food. 



They are known by the middle coxaj being rather widely sepa- 

 rated by the mesosternu«i, and by the epipleurfe being reduced 

 to a narrow thickened marginal line. Besides these essential 

 characters ot definition, other characters are seen in these insects 

 not found in the other sub-families. 



The elytra are frequently costate, and coarsely reticulate with 



