154 Trans. Acad. Sci. of St. Louis. 



teeth, which are long, very acute and prominent, the outer teeth very 

 minute and sometimes rather widely separated from the inner. Body 

 moderately large in size, depressed, shining or alutaceous, the sculpture 

 very fine; head rather small, the elytra large; outer lobe of the para- 

 glossae longer than the inner, both pointed; third maxillary palpal 

 joint long, rather blender and compressed; eyes rather well developed; 

 antennae moderately long and slender, scarcely visibly enlarged dis- 

 tally, the joints subcylindrical; neck a little less than half as wide as 

 the head; prosternum strongly carinate posteriorly; hind tarsi very 

 long and slender, filiform, four-fifths as long as the tibiae, the basal 

 joint almost as long as the next two combined; anterior tarsi slightly 



dilated, more distinctly in the male. Nearctic regions Platymedon • '8 



Labrum with the usual small median notch and four very small teeth, the 

 latter much less unequal among themselves and frequently very diflicult 

 to perceive 15 



15 — Elytra small, not longer than the prothorax ; eyes sm;.ll 16 



Elytra well developed, always longer than the prothorax, the eyes large. .17 



16 — Body minute in size, polished, sparsely punctured, the gular sutures 



wholly obsolete and traceable only by the absence of punctures on the 

 intervening surface; antennae short, the basal joint stout, the remainder 

 very slender but unusually clavate distally; neck rather less than half 

 as wide as the head; palpi short; prosternum tumid but scarcely cari- 

 nate posteriorly; hind tarsi short, moderately stout, the basal joint 

 nearly as long as the next two combined, the anterior feebly dilated. 



Caribbean region Medonella > * ^ 



Body very small in size and of slender form, shining though rather coarsely 

 and closely sculptured; gular sutures fine and sometimes subobsolete; 

 antennae longer, normal, thicker, feebly enlarged distally; neck two- 

 fifths as wide as the head; palpi longer and well developed; prosternum 

 rather strongly carinate except anteriorly; hind tarsi longer, very slen- 

 der and filiform, the basal joint distinctly shorter than the next two 

 combined; anterior tarsi slightly thickened but not at all dilated. 

 Pacific coast regions Oligopteras i "^ ' 



17 — Body moderate to very small in size, slender, more or less finely and 



closely sculptured, the gular sutures fine; head small as a rule; anten- 

 nae raiher short, moderately stout, filiform, scarcely thickened dis- 

 tally; neck two-fifths as wide as the head; prosternum strongly cari- 

 nate posteriorly; hind tarsi long and very slender, filiform, the basal 

 joint nearly as long as the next two combined, the anterior not at all 

 dilated and but feebly thickened even in the male. Pacific coast regions. 



Caloderma > 8 3s 



18 — Body moderate to small in size, rather slender, frequently dull in lus- 



tre and extremely fiuely, usually closely punctulate; head small, the 

 elytra at least as long as the prothorax; palpi well developed, the lobes 

 of the paraglossae small ; meutum unusually elongate ; gular sutures very 

 fine and remotely separated, most approximate anteriorly and thence 

 widely diverging to the base; antennae rather thick, filiform, not 

 appreciably enlarged distally; eyes well developed; neck two-fifths as 

 wide as the head ; prosternum carinate posteriorly; hind tarsi rather 

 short, somewhat stout, the basal joint longer than the second, the 



