304 MANDIBULATA. ('OI,EOPTEUA. 



the interstice broad and elevated, narrowed in front: thorax vvith the base 

 and apex truncate, rather widest a little before the middle, the base slightly 

 attenuated; disc uneven, opaque, obscurely channelled, the base of the latter 

 dilated into a triangular fovea, adjoining to which on each side, towards the 

 middle, is another transverse one : elytra unequal, also foveolated : abdomen 

 cylindric, finely punctured, with some whitish hairs towards the sides ; apex 

 obtuse, armed with four small teeth, smallest in the female : penultimate seg- 

 ment beneath in the male bifid, ivith sharp pilose lacinieE; the antepenultimate 

 notched, with an impression in front, the sides terminated in an elevated 

 ridge — in the female all the ventral segments entire : legs black, femora rather 

 thickened in the male, posterior a little bent : palpi testaceous, tipped with 

 black : antennae ferruginous, with the two basal joints black, the three apical 

 ones dusky. 



Found near London and in Devonshire ; also near Bristol. 

 " Swansea.'" — L. W. Dillwyn^ Esq. 



Genus DXXVII. — Dianous Leach. 



Antennce slightly pilose ; basal joint stout, ovate, second much smaller, 

 ovate also, third as long as the two following, linear, five following 

 decreasing in length and increasing in thickness, the remainder forming 

 a club, the terminal joint being conic. Palpi unequal, maxillary very 

 long, the third joint equalling in length the other two: lahrum subovate: 

 mandibles with a single tooth towards the apex : labium short, bilobed : 

 head large subtriangular : e^/es moderate, prominent : thorax emarginate, 

 elongate, cylindric, ovate : body oblong, punctate : abdomen margined, 

 wider than the head and thorax, terminated at the apex with two naked 

 setae; distinct and incurved in the males : legs slender: tibice simple; tarsi 

 pentamerous, the penvUtimate joint slightly bilobed. 



DianoiJs may be known from Stenus not only by the naked anal 

 processes, and abbreviated labium, but by having the inner edge of 

 the mandibles simply denticulated and not serrated; the eyes are 

 smaller, the abdomen broader, legs stouter, and the colour different : 

 — in habit, however, they resemble the Steni, as they frequent the 

 grassy banks of rivulets. 



Gends DXXVIII. — OxYPORUs, Fabricius. 



Antennce momMorm, short, clavate, the club compressed, basal joint stout and 

 long, three folio wing slender, the remaining articulations transverse, perfoliate, 

 the terminal one small, obtuse. Palpi unequal ; maxillary filiform : labial 

 with the terminal joint very large, securiform : mandibles porrect, curved. 



