392 CLASSIFICATION OF THE RHYNCHOPHOROUS COLEOPTERA. 



than in the preceding famH}^ and the mandibles thicker and 

 stronger. The epipleuraj are quite distinct, and there is no trace 

 of a h\teral fold on the inner face of the elytra. The p3'gidinm 

 is not covered bj' the elj'tra, and is impressed along its upper 

 margin for the reception of the apical edge of the el3'tra.* The 

 tibige are armed with large spurs. 



RIIYNCIIITID^. 



The peculiar form of the mandibles requires the separation of 

 these genera as a distinct ftimil^r. 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, f 



The front coxas, are usually contiguous, large and conical, in one 

 genus (Pterocolus) widely separated. The p^-gidium is either ex- 

 posed (Rliynchites, Pterocolus) or covered by the elytra (Eugnamp- 

 tus, Auletes). The epipleume are narrow, but distinct, and on the 

 inner face of the elytra remote from the margin may be seen a 

 short straight fold, the homologue of tlie well defined fold which 

 limits the lateral groove for the reception of tlie side margin of the 

 ventral segments observed in all the following families. 



Series II. ALLOGASTRA. 



Abdomen dissimilar in the two sexes ; dorsal segments 1-6 

 coriaceous or membranous, 7th large, corneous, undivided in 9 , 

 divided into two in $ ; ventral segments prolonged upwards 

 forming a sharp edge, fitting into a corres^ponding groove on the 

 inner face of the elytra, which are without epipleura^. 



The beak and oral organs vary greatly in form, as do also the 

 antennas, the tarsi, the ungues, and the position of the coxae ; the 

 1st and 2d ventral segments are most frequently connate, and the 

 3d is always shorter than the 2d ; the 5th is longer than the 4th. 



The following families seem to be indicated by the material I 

 have examined : — 



A. Auteuufe wdth a solid annulated club : 

 a. Tarsi narrow : 



Gular margin very prominent ; meutiim retracted ; " 



* Compare in this relation the curious notch in the front part of the pygidium of' 

 Anthribidre, for the reception of the sutural angles of the elytra. 



t This character was first observed by Thomson, who observes (Sk. Col. vii, 28) 

 concerning his tribe Rhyuchitina, "mandibulse depressaj, extus excisa3, intus dentataj." 



