AET. 25 MEGARIDINAE AND OANOPHsTAE — McATEE AND MALLOCH 5 



above the insertion of wing. The males have the eyes and ocelli 

 larger, and the hairs on antennae much longer than do the females. 

 Megaridinae are scarce, at least in collections, and we have not had 

 sufficient material to permit dissection to work out the structural 

 basis of classification as thoroughly as we should like. Besides the 

 charact-ers mentioned in the key to genera, we have noticed inter- 

 esting differences in puncturing of the propleurum, which are noted 

 in the descriptions, but we can scarcely say at present what taxonomic 

 value these may have. In several of the species the anterior outer 

 angle of mesopleurum is impunctate and in all there is an oblique 

 impunctate stripe running from same angle of metapleurum to a 

 short distance from posterior outer angle, which is associated with a 

 more or less evident impressed line. 



KEY TO THE) SPECIES 



1. Larger species 4.5 mm. in length and 3.75 mm. in width; antenna chiefly 



black, apical segment whitish ; practically the entire surface of pronotum 

 and scutellum with large, rather widely spaced punctures; elavus with 

 some distinct punctures ; ventral abdominal sutures impunctate ; shape of 

 head as in Figure 5; each prosternal carina almost straight, not very 

 noticeably angulate near middle, the two forming a V (fig. 3). 



majuscula, new species. 



Smaller species, not exceeding 2.5 mm. in length ; antenna otherwise colored ; 



elavus wrinkled or granulate, rarely punctate; ventral abdominal sutures 



punctate ; prosternal carinae angulate near middle, their anterior sections 



widely divergent 2 



2. Vertex, pronotum, and disk of scutellum entirely impunctate, the scutellum 



distinctly punctate on sides ; long hairs of male antenna scarcely as long 

 as the segment bearing them ; meso- and meta-sterna impunctate, anterior 



lateral angles of mesopleurum impunctate and striate laevicoUis Sta.1. 



Pronotum with distinct punctures on some part of its surface 3 



3. Pronotum and scutellum each with a large bright red discal spot, that on 



scutellum sometimes longitudinally divided by a black line; shape of 

 head, as in Figures 12, 15 ; some of the hairs on antenna of male nearly 

 as long as the segments bearing them (fig. 4) ; meso- and meta-sterna 

 coarsely striato-punctate ; mesopleurum punctate almost to lateral edge. 



trinotata Distant. 

 Pronotum and scutellum unicolorous, castaneous to black 4 



4. Pronotum and scutellum punctate almost throughout 5 



Pronotum not so uniformly, and scutellum less decidedly punctate 7 



5. Pronotum distinctly more than half as long as wide; outline of insect as 



seen from above and the side as in Figures 1 and 13 ; length 1.5 mm. 



longula, new species. 

 Form less elongate (in fact, almost hemispherical) ; length 2 mm. or more__6 



6. Scutellum quite, and pronotum less, conspiculously wrinkled, with rows of 



punctures between the wrinkles nigritula Stal. 



Dorsum punctate but not wrinkled punctulata Horvath. 



7. Pronotum without group of punctures on that part just behind head and 



no transverse series on disk 8 



Pronotum with punctures on that part just behind head, and a more or less 

 pronounced band of punctures across disk 9 



