LUCANIDAE. 235 



trochanters not prominent internally; anterior tibicTC more 

 or less toothed externally, frequently palmate, with one ter- 

 minal spur; middle and posterior tibia3 with two external 

 teeth, terminal dilatation, and two spurs ; tarsi slender, 

 5-jointed, last joint long; claws simple, with a short inter- 

 mediate onychium bearing two bristles. 



The insects of this family live on the juices of decomposing 

 wood, and are very closely allied to the Scaraliseidas ; the i)rin- 

 cipal distinguishing character is that the outer joints of the 

 antennae, thougli somewhat lamellate, cannot be placed closely so 

 as to form a compact club. In the position of the abdominal 

 spii'acles the tribe Lucanini resembles the first sub-fandly of the 

 Scai'abieidae, in which alone occur tribes with the pygidium en- 

 tirely covered by the elytra, as in the present family. In fact, 

 for a distinguishing character from some of the tribes, reliance 

 nmst be had on the large size of the uieutum, and the form of the 

 antennal club. 



They form two tribes, distinguished by the form of the mentum 

 and position of the ligula. Those portions of the body in the 

 second tribe recall strikingly the form already seen in the Cara- 

 bida3, with which, however, the insects have no other resemblance. 



Mentum entire, ligula behind or at tlie apex of the mentum. Lccamni. 

 Mentum deeply emarginate, ligula filling the emargination. Passalini. 



Tribe I.— LUCAXINI. 



Ligula membranous or coriaceous, usually behind the mentum, 

 which is entire; mandibles without a basal molar tooth, usually 

 elongated in the males; external lobe of the maxillte unarmed, 

 pcnicillate; labrum connate in the first sub-tribe, free in tlie other 

 two; scutellum between the elytra; middle coxa? somewhat trans- 

 verse. 



The species are usually large oblong insects, glabrous above, 

 sometimes cylindrical. 



Sub-tribes, all having the thorax not closely applied to the 

 elytra, are represented in our fauna as follows: — 



Ligula and maxilL-e covered by the mentum ; 



Anterior coxae approximate ; antenn;e geniculate. Lucanini. 



Anterior coxae contiguous ; antennje straight. Ckruchim. 



Ligula and maxillse not covered ; antennae straight. Sinodendrini. 



