Stenus.l STAPHYLINIDJ). 331 



b. Elytra not as tliiokly punctured as thorax, 



which is broader in proportion S. LUSTEATOR, Er. 



II. Posterior tarsi short, hardly lonj^er than half the 

 tibia}, first joint about equal to last. 

 i. Le^s entirely black. 



1. Segments 2-5 of hind body each furnished with 



four little raised longitudinal keels at base. 



A. Elytra uneven, with evident depressions, 



a. Head almost as broad as elytra. 



a*. Thorax and elytra strongly and rather 



thickly punctured ; elytra as long as 



thorax ' S. bupthalmtjs, Grau. 



h*. Thorax and elytra coarsely and not 

 • thickly punctured ; elytra a little longer 



than thorax S. MEL4NOPTTS, Marsh. 



b. Head evidently narrower than elytra. 



a*. Head hardly broader than thorax . . S. INCEASSATUS, Er. 

 h*. Head evidently broader than thorax, 

 af. Interval between the frontal fur- 

 rows broad, not raised in a keel ; 

 thorax without trace of central 



furrow S. melanaeifs, Steph. 



(cinerascens, Er.). 

 bf. Interval between the frontal furrows 

 raised, more or less keeled ; thorax 

 with obsolete central furrow . . . vS. atratulus, Er. 



B. Elytra even or almost even, without, or with 



very obsolete, depressions, except at suture. 



a. Thorax cliannelled for the greater part of 



its length, 

 a*. Upper suface rather dull, less strongly 



punctured S. CANALlCTTLATtrg, Oyll. 



b*. Upper surface shiny, more strongly 



punctured S. nitens, Steph. 



[(emulus, Er.). 



b. Thorax without central channel . . . . S. moeio, Orav. 



2. Front segments of hind body with one small 



longitudinal keel situated in centre of base. 



A. Elytra very uneven, much longer than 



thorax S. PUSILLUS, Steph. 



B. Elytra much less uneven, scarcely longer 



than thorax S. EXIGUUS, Er. 



3. Base of front segments of hind body simple ; 



elytra a little longer than thorax ; upper sur- 

 face rather thickly pubescent S. INCANUS, Er. 



ii. Legs more or less light, never black. 



1. Hind body with very feeble margins ; legs dark 



ferruginous, or brownish, with knees darker . . S. FTJSCIPES, Orav, 



2. Hind body with rather strong margins. 



A. Legs light, testaceous ; base of front seg- 



ments of hind body with one small central 



longitudinal keel S. cieculabis, Orav. 



B. Legs darker, more or less pitchy. 



a. Base of front segments of hind body with 

 four small keels ; front parts more coarsely 

 punctured ; thorax longer with sides less 

 rounded S. vafellus, Er. 



