114 Trans. Acad. Sci. of St. Louis. 



Eulathrobiuni n. gen. 



We begin here a series of genera differing radically from 

 those which precede in having a strong carinif orni line on the 

 flanks of the elytra, parallel to and not far from the lower 

 edo-e. This very important character has been referred to 

 previously by several authors, notably Dr. Sharp, in ex- 

 pounding the Amazonian and Mexican Paederini, but I am 

 not aware that it has been employed hitherto in defining 

 o-enera. The genera without this line are more boreal in 

 habitat and equally characteristic of the old and new world 

 subarctic faunas, but those possessing the line are more 

 southern in habitat, as a rule, and probably originated in 

 America; only one genus — LohratJiium 'Ro.y , — is common 

 to the nearctic and palaearctic regions of the globe, and this 

 is more northern in its range than any other, probably 

 crossing from America to Asia by way of Bering Strait. 

 The o-enus Eulathrobium consists at present of a single 

 species, one of the largest and finest of our Lathrobia; it may 

 be described as follows: — 



Form broad, parallel and somewhat feebly convex, deep black throughout 

 the legs dark brownish-rufous, the antennae and palpi black, with the 

 joints rufous at base; lustre shining; head well developed, wider than 

 long, broadly arcuato-truncate at base, the angles very broadly rounded, 

 the sides becoming parallel and broadly arcuate behind the eyes, which 

 are moderately large, the punctures rather coarse and close-set 

 throughout, excepting a small smooth area on the vertex; autennae fili- 

 form, moderately stout, about as long as the head and prothorax, the 

 medial joints three-fourths longer than wide, obconic, a little shorter 

 in the female; prothorax not quite as v?ide as the head and only very 

 slightly longer than wide, broadly suboval, the sides feebly converging 

 and arcuate posteriorly from the very broadly rounded and obsolete 

 apical angles, the punctures coarscj deep and not very sparse, the 

 median smooth line distinct, narrow, not defined by series; elytra large, 

 quadrate, parallel, distinctly wider than the head especially in tbe 

 female, about a third wider than the prothorax and a fourth longer in 

 the male, nearly a third longer than the prothorax in the female, the 

 punctures moderately coarse, strong, unusually close-set and arranged 

 without trace of order, the surface shining; abdomen parallel and 

 straight at the sides, but little narrower than the elytra, finely, rather 

 closely punctured but somewhat shining; legs rather long, only moder- 

 ately stout. Male with the fifth ventral somewhat broadly and feebly 



