318 On a new Genus of Lamellicorn Beetles. 



faunas indicate that they have not always been separated 

 as completely as they now are. The representatives of the 

 group in Australia and South America respectively are very 

 closely related, and the new form here described is the most 

 isolated yet known. While differing little from Phcenognatha 

 and Aclopusm the essential features of the group (the peculiar 

 development of the mandibles and labrum, the reduction of 

 the maxilla? and labium and of the number of joints in the 

 antenna), in other characters common to all the hitherto- 

 known species (the greatly reduced abdomen, long meta- 

 sternum, and consequent far-back position of the hind legs, 

 and the extreme slenderness of the tarsi) it differs entirely. 

 It is also peculiar in the great size of the club of the antenna, 

 a feature, of course, distinctive of the males, and also in a 

 still more interesting particular, in all probability peculiar 

 also to that sex, viz., the cleft inner claw of the front foot. 

 The absence of the female is another significant point of 

 agreement with Phcenognatlia and Aclopm, of which only a 

 single female specimen has yet been recorded, although the 

 species appear to be fairly numerous. Probably in all the 

 genera the females are sluggish and of quite different habits 

 to the males. 



Xenaclopus, gen. no v. 



Corpus latum, ubique erecte ciliatum. Caput breve, oculis desuper 

 visis parvis, lateraliter haud prominentibus. Clypeus brevissiraus, 

 antice late arcuatus. Labrum valde porrectum, corneum, fere 

 semicirculare. Mandibula? detecta?, fere semicirculares, haud 

 acuminata? aut dentata?, supra concava?. Maxilla? multo reducta?, 

 mutica?, palpis longis, 4-articulatis. Mentum solidum, acumina- 

 tum, palpis termiualibus, longis. Omnium palporum articulus 

 ultimus longissimus. Antenna? 9-articulata?, clava triphylla. 

 Pedes validi. Coxa? grandes eontigua?, antica? latissima?, intus 

 prominentes. Femora 4 posteriora lata. Tibia antica fortiter 

 ;'>-(lentata, posteriores extus transversim cariuata? et spinosa?. 

 Tarsi longitudine ad tibias fere a?quales. Abdomen subtus 

 6-articulatum, paulo contractum. 

 J , antennarum articuli 3 ultimi grandes, longitudine ad stipitem 

 a?quales, basi angusti, deinde valde dilatati ; pedum anticorum 

 unguis internus profunde fissus. 



Xenaclopus borneensis, sp. n. 



Parvus, breviter oblongus, castaneus, nitidus, capite, scutello, 

 elytrorum sutura et marginibus externis abdomineque nigris ; 

 corpore toto cum pedibus longe sed sparsim erecte eiliato ; capite 

 laxe rugoso, pronoto et elytris grosse a?qualiter baud crebre 

 puuctatis, punctis piliferis : prouoto leviter conyexo, lateribus 



