892 CLASSIFICATION OF THE RHYNCHOPHOROUS COLEOPTERA. 
than in the preceding family, and the mandibles thicker and 
stronger. The epipleurz are quite distinct, and there is no trace 
of a lateral fold on the inner face of the elytra. The pygidium 
is not covered by the elytra, and is impressed along its upper 
margin for the reception of the apical edge of the elytra.* The 
tibiæ are armed with large spurs. 
RHYNCHITID&. 
The peculiar form of the mandibles requires the separation of 
these genera as a distinct family. The teeth on the inner side are 
well developed as usual, but in addition, the apex is prolonged out- 
wards into an acute process, behind which is another large tooth. t 
The front cox are usually contiguous, large and conical, in one 
genus (Pterocolus) widely separated. The pygidium is either ex- 
posed (Rhynchites, Pterocolus) or covered by the elytra (Eugnamp- 
tus, Auletes). The epipleure are narrow, but distinct, and on the 
inner face of the elytra remote from the margin may be seen 4 
short straight fold, the homologue of the well defined fold which 
limits the lateral groove for the reception of the side margin of the 
ventral segments observed in all the following families. 
Serres II. ALLOGASTRA. 
Abdomen dissimilar in the two sexes; dorsal segments 1-6 
coriaceous or membranous, 7th large, corneous, undivided in @> 
divided into two in ĝ ; ventral segments prolonged upwards 
forming a sharp edge, fitting into a corresponding groove on the 
inner face of the elytra, which are without epipleure. 
The beak and oral organs vary greatly in form, as do also the 
antenne, the tarsi, the ungues, and the position of the cox ; the 
lst and 2d ventral segments are most frequently connate, and the 
3d is always shorter than the 2d; the 5th is longer than the ben’ 
The following families seem to be indicated by the material I 
have examined :— 
A. Antenne with a solid annulated club: 
rrow : 
Gular margin very prominent; mentum retracted ; 
of 
* Compare in this relation the curious notch in the front part of the your 
An dæ, for th ption of th tural angles of the elytra. i vi, 9) 
ł This character was first observed by Thomson, who observes (Sk. Col. pa x“ 
f hitina, “mandibulæ d p j t excise, intus denta 
