COLEOPTERA. 185 



elytra of artus, is not, to the best of my knowledge, due entirely to 

 immaturity, but is a feature of the mature insect. 



The distinguishing characters belonging to the three species, dilu- 

 tus, artus, and obsoletus, are in the punctuation of the elytra, which 

 is much the finest and closest in the last, and in the structure of the 

 prothorax, which renders artiis immediately recognizable. The sexual 

 characters are strikingly uniform throughout the series. 



29. A. meridionalis n. sp. (Schwarz MS.). — Form slender, sub-cylin- 

 drical. Pubescence rather sparse, short, evenly distributed, sub-recumbent, 

 cinereous, rattier inconspicuous. Entire body moderately shining. Head 

 rather robust, scarcely twice as wide as long; interocular surface scarcely one- 

 third wider than the eye, nearly flat ; sulcations almost entirely obsolete ; 

 punctures rather sparse and irregularly distributed : ocular lines meeting 

 at less than one length in advance; eyes very prominent : antennae short, 

 scarcely longer than the width of bead, piceous-brown, darker toward tip, 

 slender, club strong ; third joint one-fourth longer than the fourth, eighth more 

 robust than the seventh, last joint of club as long as the eighth and ninth 

 together; basal joint of antenna slightly paler ; maxillary palpi very long 

 and slender, almost as long as the antenna, flavate, tip of third joint slightly 

 darker. Prothorax arcuately, evenly, and very gradually increasing in -width 

 to the middle, where it is one-eighth narrower than long and scarcely three- 

 fourths as wide as the head ; sides thence equally convergent posteriorly 

 and feebly sinuate ; anterior and posterior margins sub-equal in length and 

 curvature; surface finely and somewhat confusedly punctate; punctures 

 tending to coalesce transversely. Elytra at base equal in width to the head, 

 or but very slightly narrower : sides parallel, slightly longer than the width 

 at base, nearly straight toward the humeri, slightly arcuate toward the 

 apices ; together roundly and rather strongly emarginate behind ; suture 

 slightly longer than the pronotum ; surface ratber strongly impressed on the 

 suture toward the base; punctures large, close, nearly evenly distributed, 

 distant by about one-half their widths. Abdominal segments decreasing 

 uniformly and just perceptibly in width, first much narrower than the con- 

 tiguous elytra, cylindrical ; border obsolete ; strongly constricted toward the 

 base ; surface coarsely, closely, and evenly punctate ; punctures larger than 

 those of the pronotum, deeply impressed, almost polygonally crowded ; trans- 

 verse carinae not cusped. Legs somewhat long, very slender, uniformly pale 

 piceous-brown ; first joint of the posterior tarsi not as long as the next two 

 together ; fourth joints strongly bilobed, lobes very narrow. 



Male. — Posterior edge of the fifth ventral segment just visibly emarginate 

 in its middle sixth at apex, einargination rounded and excessively feeble ; 

 sixth segment very deeply and somewhat narrowly incised at apex, incisure 

 extending anteriorly through two-thirds of the segment, angle slightly 

 rounded, sides nearly straight, exterior angles slightly rounded, slightly 

 more than twice as deep as wide ; seventh triangularly emarginate at tip. 



Female. — Sixth segment strongly, broadly, and somewhat angularly rounded 

 behind ; seventh acuminate at tip. 



Length 2.3-2.7 mm. 



