AMERICAN COLEOPTERA. 213 



Hind le,2;s remarkably large; trochanter large, on the inner side of 

 the base of the thigh, quadrilateral, with the inner posterior angle 

 acute; thighs very thick, extending to the tip of the abdomen, con- 

 cave beneath, with a large obtuse tooth on the inner and outer margins 

 of the concavity, nearer the base than the middle. Tibiae as long as the 

 thighs, rather slender, much curved and twisted, so as to adapt them- 

 selves to the inner part of the inferior surface of the thigh in repose; 

 thickened at tip, produced inwards, and armed with a short acute pro- 

 cess, but no articulated spurs; terminal surface large, reniform, acutely 

 margined, and clothed with long dense yellow hair; tarsi inserted at 

 the inner side in the emargination of this reniform corbel; quite simi- 

 lar to those of the middle legs, but capable of being folded against the 

 inner side of the tibi;ie. 



A very slight examination of the combination of characters above 

 described, will show that this insect cannot properly be considered a 

 member of any of the families, or even series of families of Coleoptera, 

 as at present constituted. 



A detailed analysis of the systematic value of the structure of the 

 different organs, will show on the other hand, that it is related to 

 several of the series of families; though, as I hope to demonstrate, in 

 different degrees, and in a somewhat different manner to any opinion 

 hitherto offered for consideration. 



The mentum is a broad flat plate, not coriaceous in front; the ligula 

 is extremely small and corneous without paraglossae ; these forms occur 

 in several sections of the Coleoptera, especially in the Clavicorn series ; 

 at any rate, they do not indicate Cerarabycide but rather Clavicorn 

 relationships. The large terminal reniform palparium occurs in almost 

 every genus where the last joint of the palpi is triangular, and does 

 not therefore indicate anything of special import; neither do the small 

 maxillary lobes, which seem to be equally but feebly developed. 



The mandibles on the contrary are extraordinarily suggestive. The 

 vertical and outward movements above described are found only in 

 Khyuchophora; where they appear in the Balauinidfe, with purely 

 vertical motion, and in some of the Calandridie with outward motion. 

 The slight undulation of the lower edge indicates the lower tooth of 

 the normal Khynchophora, while the broad external lobe represents the 

 upper touth in the position, in which it would be in several Khyncho- 

 phora, if slightly changed by rotation outwards as in Calandridte, and 

 which it actually has in Rhynchitidae. The narrow elongate head, 

 inserted into the prothorax by a globose articulation is also sugges- 

 tive of Uhynchophorous alliances; while the peculiar impressions of 



