June .000] CaS^Y 1 On NORTH AMERICAN C. LEOPTERA. 59 



which are notably smaller, the shorter tarsi, and especially, because of 

 the radically different form of the post-coxal plates of the abdomen. 

 These plates in Scaphisoma are very short and only developed inter- 

 nally, the bounding arc extending outward externally, very gradually 

 approaching the base of the segment, while in Scaphiomicnis the plates 

 are more nearly semi-elliptic, having the outer part of the bounding 

 curve directed upon the base without change of direction toward the 

 sides of the body, somewhat, in fact, as in the subgenus Pullns of the 

 Coccinellidje. The species are all very much more minute than in 

 Scaphisoma, and those which are represented before me may be dis- 

 tinguished by the following characters : — 



Abdominal plates ahnost evenly parabolic in form, the apex more broadly rounded 

 and the outer side more arcuate and approaching the base scarcely less obliquely 



than the inner side ; sutural line of the elytra not flexed outward basally 2 



Abdominal plates more narrowly rounded at apex, the external branch of the bound- 

 ing curve much less arcuate than the internal, and directed almost perpendicu- 

 larly upon the base ; sutural line of the elytra flexed outward at base, parallel to 



the basal margin ; elytra blackish, gradually and broadly pale toward tip 5 



2_Elytra bicolored, black in about basal half, the remainder rufous 3 



Elytra pale throughout ^ 



3-lAbdominal plates extending much beyond the middle of the segment, the 

 punctures and the reticulations of the segment almost effaced ; form rather short 

 and stout. Length 0.8-0.95 mm-; width 0.55-0.65 mm. North Carolina (Ashe- 



..,, . pusillus Z^r. 



Abdominal plates not quite extending to the middle of the segment, the surface of 

 which is distinctly reticulate and finely, sparsely punctulate ; metasternum strongly, 

 though sparsely, punctate; body slightly larger, the elytra destinctly longer when 

 compared with the prothorax. Length i.i mm.; width 0.7 mm. Rhode is- 



tand (Boston Neck) dimidiatus, sp. nov. 



4— Entire body and legs pale fulvo-testaceous throughout, the form more narrowly 

 oval ; abdominal plates broadly rounded, not extending quite to the middle of 

 the segment; metasternal punctures minute and very feeble. Length 0.9 mm.; 



width 0.6mm.; Michigan,— Mr. Schwarz flavescens, sp. nov. 



5— Sutural line of the elytra extending outward along the base to inner third 6 



Sutural line extending nearly to the middle of the width ; body more minute and less 



oval. 



■7 



6— Abdominal plates relatively larger, extending to the middle of the segment ; body 

 blackish, the legs, antenna and apical half of the abdomen pale; elytral punctures 

 sparse but rather distinct, eff"aced as usual toward base. Length 0.85 mm.; 

 width 0.57 mm. Lake Superior lacustris, sp. nov. 



Abdominal plates very small, extending but little beyond basal third of the length, 

 narrowly rounded at apex ; body in coloration and sculpture nearly similar to 

 lacustris, the outline a little more broadly oval. Length 0.9 mm.; width 

 065 mm. Iowa (Keokuk) nugator, sp. nov. 



