246 MEMOIRS ON THE COLEOPTERA 



Isolomalus Lewis 



A few species alone constitute this genus within our boundaries, 

 but in the warmer parts of North America the species become very 

 numerous. Bistriatus and seminulum are widely diffused over the 

 Atlantic regions and mancus is abundant from northern California 

 to British Columbia; debilis Lee. from Colorado seems to be allied 

 to mancus but apparently is smaller and has much finer punctua- 

 tion. Complexus Csy., is allied to seminulum but is more elongate; 

 since describing the unique type, having very remarkable pygidial 

 characters, I have received another specimen, with simple pygidium, 

 from Louisiana. In seminulum there is very little sexual difference 

 in the pygidium, this being convex, very smooth and evenly punc- 

 tulate, but in two examples at hand there are also a few fine irregular 

 discal scratches. In teres Lee., the female pygidium has a rounded 

 central area covered loosely with very irregular coarse scratches. 

 The four following species seem to be new: 



*Isolomalus nanulus n. sp. Narrowly oblong-oval, strongly convex, 

 polished, deep black, the legs obscure rufous; head evenly and feebly 

 convex, extremely minutely, sparsely punctulate, with the apical margin 

 strongly beaded throughout; prothorax long and barely two-fifths wider 

 than long, the moderately converging sides broadly arcuate, gradually 

 though only slightly, more so anteriorly, the marginal line fine, entire, 

 curving inward slightly at base; surface with very fine, well separated 

 and uniform punctuation; elytra slightly elongate, two-thirds longer 

 than the prothorax, narrowed at apex, with strongly and subevenly 

 arcuate sides; sutural stria distinct, abbreviated at apical third but 

 -attaining the apex; there are also two oblique discal striae extero-basally; 

 the very fine lateral line is arcuate downward as usual in the genus; 

 sides of the metasternum and abdomen rather strongly, not very closely 

 punctate, the mes-episterna almost impunctate; anterior tibiae with the 

 arcuate external edge bearing four extremely minute spicules; pygidium 

 convex, even, shining, finely punctulate, unmodified in the types at 

 hand. Length 1.6-1.8 mm.; width 0.8-0.9 mm. Cuba (Havana), Baker. 

 Six examples. 



Much smaller in size, apparently, than either of the other two 

 species described thus far from Cuba. 



Isolomalus ovulatus n. sp. Evenly elongate-oval, strongly convex, 

 polished, piceous-black, the legs dull rufous; head evenly, feebly convex, 

 extremely minutely punctulate, the apical beading entire; prothorax 

 fully one-half wider than the median length, the sides strongly converging 

 from base to apex and very evenly and rather feebly arcuate throughout, 

 the apical angles very acute, the sinus deep; beaded side margins rather 



