BEMBIDIIN.E 37 



Group VI planatum 

 Subgenus Melomalus nov. 



This group is composed of a moderate number of species, occur- 

 ring only in the western parts of the continent, and agreeing very 

 well in certain features of habitus. The body is oblong, notably 

 depressed on the upper surface, with the elytral striae entire, sub- 

 equally strong throughout the width as a rule, the seventh always 

 evident and frequently almost as deep as the sixth. The color is 

 usually deep black, without evident metallic lustre, and the elytra 

 are never variegated or maculate. The mentum tooth is generally 

 well developed, triangular, with broadly rounded and obtuse tip 

 but, in the singular extensum type, is extremely short and broad, 

 with the apex obtuse. The two dorsal foveae of each elytron ad- 

 here to the inner side of the third stria as a rule, rarely becoming 

 detached, and vary from moderate in size to large and impressed, 

 as in the second section of the preceding subgenus. The species 

 planiusculum and complanulum of Mannerheim, of Sitka and Kad- 

 jak, Alaska, respectively, belong to this group, but I must hold 

 the latter to be different from anything before me at present; the 

 former is said to have a greenish margin of the subquadrate pro- 

 notum and large deep elytral foveae; its dimensions are said to be 

 4 by 1.5 mm. The latter is nigro-aeneous in lustre, the prothorax 

 twice as wide as long and the elytral foveae small; it is 3.3 by 1.3 

 mm. in size and is probably different from any of the numerous 

 allied California forms. 



The species at hand form three very distinctly limited sections 

 as follows: 



Xeck short; body large; elytra broad, alutaceous, the prothorax but 

 slightly transverse; striae barely impressed, the inner with very fine 

 irregular and close-set punctulation; foveae rather large; legs and 

 tarsi very long and slender. Section MELOMALUS in sp 2 



Xeck short; body small, narrower, the elytra polished; prothorax decid- 

 edly transverse; striae deeply impressed as a rule, impunctate; foveae 

 small or large; tarsi moderate. Section MICROMELOMALUS nov. . .4 



Neck long; body very elongate, more or less depressed, the elytra pol- 

 ished; prothorax subcordiform, barely wider than long; striae im- 

 punctate, the foveae moderate; tarsi rather long, very slender. 

 Section TRACHELONEPHA nov 10 



2 Prothorax sinuate at the sides basally, the sides becoming parallel in 

 basal fifth or sixth. Body broadly oblong, depressed, black, pol- 



