496 On Aquatic Carnivorous Coleoptera or Dytiscide. 
Group 2. 
Outline ofthorax either slightly discontinuous, or continuouswith thatofthe elytra; 
prosternal process comparatively broad, nearly flat, evenly and distinctly margined, 
shining and impunctate; metasternal groove moderately broad. Hind coxee never 
large; wings of metasternum large; coxal lines deeply impressed in their upper 
part, much prolonged in the anterior and outward direction; hind legs slender or 
moderate (never stout), their femora little thickened, the postero-external angle 
slightly obtuse, sometimes rectangular, Male fore feet but little developed, clothed 
beneath with very short “glandular” pubescence ; sexual differences of sculpture 
slight. 
Seventeen species from both Old and New Worlds. 
668. Agabus hypomelas, Mann., M.C.—Oblongo-ovalis, niger, nitidus, antennis 
pedibusque rufis, supra sat conspicue nescens, capite anterius, prothoracis 
lateribus versus angulum anteriorem, elytrorumque epipleuris vage rufescentibus ; 
elytris dense subtilissime reticulatis subtiliusque punctulatis; metasterni impressione 
brevi. Long. 8, lat. 43 m.m. 
In this species the lateral margin of the thorax is rather fine, and the thorax is 
rather straight sided, the hind angles being nearly rectangular. The male has the 
three basal joints of the front and middle tarsi shehtly thickened, and turnished 
beneath with short glandular hairs. The exact position of this species is not easy 
to define, the prosternal process is short and broad, but is very teebly punctulate 
at the sides, the metasternal cavity is unusually short, and the coxal lines are not 
greatly divergent in their upper part ; the side wings of the metasternum are shorter 
than in Dytiscus guttatus (No. 670). 
North America, (Sitkha, Vancouver's Island). 737. 
669. Agabus styriacus, n. sp.—Oblongo-ovalis, latiusculus, parum nitidus, niger, 
supra subzenescens, antennis palpisque rufis, pedibus piceis, tarsis rufis, elytris guttis 
duabus testaceis; prothorace lateribus obliquis, basi quam apice latiore, angulis 
posterioribus rectis ; elytris undique punctato-rugosulis. Long. 83, lat. 42 m.m. 
The surface of the wing-cases in this species, is rendered rough by a dense, fine, 
indefinite sculpture which can scarcely be called punctuation; in the male, even 
on the base of the elytra with a high magnifying power, this sculpture does not 
~ assume the form of reticulation, but in the female the sculpture is rather coarser 
and deeper, and gives the appearance of very obscure reticulation and dense 
rugulosities combined. In the male the three basal joints of the front tarsi are 
