128 MEMOIRS ON THE COLEOPTERA 



parallel throughout, with straight sides and rather thick margins, evi- 

 dently narrower than the prothorax, the fourth and fifth tergites equal, 

 the first two equally and deeply impressed transversely at base, the third 

 not impressed but with a fine and obsoletely subimpressed line along the 

 basal margin; middle coxae well separated, the small but narrowly 

 parabolic metasternal projection separated from the rather obtuse point 

 of the long mesosternal process by a relatively short deep interval; first 

 three joints of the hind tarsi decreasing rapidly in length. Length 

 2.4 mm.; width 0.6 mm. California (Napa Junction). 



Differs from densissima in the longer third antennal joint, in 

 the deep and not "schwach" impressions of the first two tergites 

 and in some other minor features. This and the aberrant diserticola 

 are the only species in my collection agreeing with the generic 

 diagnosis in having no concavity at the base of the third tergite; 

 two sections in the genus are therefore apparently indicated. 



Paradilacra erebea n. sp. More slender and rather less convex, nearly 

 parallel, a little less dull in lustre, the minute punctures close-set through- 

 out; color piceous-black, the head and abdomen deep black, the legs in 

 great part piceous-black; pubescence fine, very short, dusky, not at all 

 sericeous; head smaller, not quite three-fourths as wide as the prothorax, 

 nearly as long as wide, the eyes large, at about two-thirds their length 

 from the base, the tempora only just perceptibly more prominent and 

 evenly rounded, converging slightly upon the eyes; antennae only 

 moderately long and notably slender, piceous-black, gradually and very 

 feebly incrassate, the third joint distinctly shorter than the second, the 

 next five distinctly elongate, the ninth and tenth subequal and just 

 visibly shorter than wide, the last slightly shorter than the two preceding; 

 prothorax nearly two-fifths wider than long, subparallel, the sides very 

 feebly and broadly arcuate, becoming slightly straighter but not definitely 

 converging basally, the base feebly impressed before the scutellum; 

 elytra moderately transverse, only a sixth or seventh wider, the suture 

 about a third longer, than the prothorax; abdomen distinctly narrower 

 than the elytra, parallel, narrowing very slightly at tip, the abdominal 

 impressions more shining than the rest of the surface. Length 2.4 mm.; 

 width 0.48 mm. California (Napa Junction and near Mt. Diablo). 



Distinguishable at once from the preceding and densissima, 

 in having the basal impressions of the first three tergites broadly 

 concave, deep and equal; it thus represents a different section of the 

 genus. 



Paradilacra subaequa n. sp. Moderately stout and convex, subparallel, 

 extremely minutely and densely punctate, dull and black throughout, 

 the legs piceous-black; head notably small, two-thirds as wide as the 

 prothorax, but little wider than long, the eyes, oblique, only moderate 

 and at rather more than their own length from the base, the tempora a 



