376 CLASSIFICATION OF THE CARABUWE 



observation, has stated the last joint to be small and subulate : had he taken the trouble 

 to observe the number of joints preceding his last joint, ho would have seen that the latter 

 was no joint at all, but merely the obliquely pointed apex. Chaudoir seems to have been 

 the first to separate them into a distinct group, without, however, pointing out the precise 

 characters by which they may be distinguished, and without any remarks upon their affi- 

 nities, which are, indeed, extremely obscure; Solier has placed them near Casnonia?. To 

 the insects of the preceding division they have but little resemblance, although there is 

 a slight analogy to be found in Diaphorus, not only in the form of the head and thorax, 

 but also in the extension of the 9th stria of the elytra around the apex, so as to meet the 

 sutural stria. The paraglossrc are linear, and much longer than the ligula. 



f. Odacanthse. 



This is the first of the numerous groups of this division, the principal common charac- 

 ter of which seems to be that the three basal joints of the antenna? are evidently of a dif- 

 ferent nature from the others, more polished, and usually entirely glabrous. The chief 

 exceptions to this last character are found in the present group, where, in some of the ge- 

 nera, the antenna? are hairy even to the base, but by close inspection the difference in ap- 

 pearance between the 3d and 4th joint can always be recognised. In this series, this 

 group is readily known by the large rhomboidal head inserted into the thorax by a small 

 neck, and by the long and cylindrical thorax. The form of the elytra is variable, but they 

 are always truncate to some extent: the anterior tibia? are slender, and not spinous at the 

 tip; their spurs appear distinct: the tarsi are sometimes broad, sometimes narrow, their 

 fourth joint is more or less emarginate: the claws are variable in form. 



Five species are cited as inhabiting the United States: Casnonia Pcnsylvanica and Lep- 

 totrachelus dorsalis, are the only ones known to me : the others are C. p i c t a Chaud., Bull. 

 Mosc, 1848, C. ludoviciana Salic, Ann. Ent. Soc. Fr. 1849, and C. rufipes Dcj. 

 The last is placed by Chaudoir in his genus Apiodera. 



g. Lcbiw. 



A very extensive group, comprising the greater part of the " Truncatipenncs" of Dcjean, 

 and consisting of insects, which, though somewhat differing in form, arc related by very 

 strong joints of resemblance, and connected by insensible modifications of structure. The 

 elytra are always truncate at the extremity, and the anterior tibia? are slender and scarcely 

 spinous at the extremity: their terminal spurs are sometimes distinct, sometimes obsolete. 

 The first three joints of the antenna? appear to be always very smooth and glabrous. The 

 head, tarsi, and ungues are variable in form, even among closely allied genera. The an- 

 terior tarsi of the male are slightly dilated, and furnished beneath with scries of papilla?. 

 The maxillary palpi are always filiform. 



For the more convenient analysis of the genera, wc may divide the group into three 

 tolerably well defined portions. 



Mcntum dentc medio indistincto, membrana basali velato. 



1. Caput postico constrictum ; palpi labialea non dilatati. 



2. Caput postico vix constrictum; palpi prrecipuc acuminati. 



3. Mcntum dente magno, distincto: palpi maxillarcs semper truncati: labiales dilatati: caput 

 postice vix constrictum. 



