HYDMOSYNE. 173 



Labrum subcircular. 



Mandibles (Tab. VII. fig. 4o) robust, acuminated at the apex; the 

 inner surface near the base is subsinuate, and forms two obsolete 

 inner teeth. 



Maxillary palpi (Tab. VII. fig. 4 m) elongate, dilated at the apex ; 

 the basal joint is minute ; the second attenuate, thickened towards 

 the apex ; the third joint in breadth double that of the second, 

 gradually inflated towards the apex ; the terminal joint is abbreviated 

 and conical. 



Labial palpi (Tab. VII. fig. 4 I) minute, robust, subcylindrical ; 

 the penultimate joint being slightly thickened at the apex, and the 

 terminal joint more slender. 



Antenna; approximate, situated between and below the inner 

 surface of the eyes, filiform, robust ; the basal joint elongate and 

 broadly dilated (more broadly than in the preceding genus, Ex- 

 artematopus) ; the second narrower, and minute ; the third joint 

 longer than the first, and attenuate ; the fourth and fifth thicker 

 and subequal. 



Eyes large and subglobose, situated at the base of the head, ex- 

 tending laterally not so far as the anterior angles of the thorax. 



Head transverse (slightly produced in front), hardly more depressed 

 in front than the thorax, porrect. 



Thorax broader than the head, transverse, obsoletely excavated 

 in front ; the sides subconstricted towards the apex and marginate ; 

 the surface generally finely punctate and glabrous or sparingly pu- 

 bescent. 



Scutellum distinct, triangular. 



Elytra subparallel, slightly broader than the thorax, punctate or 

 punctate-striate, subpubescent or glabrous. 



Legs: the anterior femora robust. The tibice incurved at their 

 immediate base and gradually thickened towards the apex. The tarsi 

 are elongated ; the basal joint is triangular, not quite so broad as the 

 apex of the tibiae ; the second of the same form, but more minute ; 

 the third broad, and almost bilobed ; the apical joint is elongate, 

 inflected, and gradually thickened ; the terminal claw is bifid, and 

 armed on its inner surface on either side with a second, more minute 

 tooth. The posterior femora are broadly incrassated, gradually 

 tapering towards the apex. The tibice are short, inflected at the 

 immediate apex ; the posterior surface is longitudinally grooved, and 

 terminates in a deeply marginate socket for the insertion of the an- 

 tenna? ; this socket commences in an obtuse angle in the margination, 

 is armed along its sides with a closely arranged series of comb-like 

 teeth, and terminates ultimately in a double incurved claw (the outer 



