384 On Aquatic Carnivorous Cohoptera or Dytiscida;. 



357. Hyphydrus contiguus, Wehncke, Stet. Zeit. 1877, p. 150.— Anguste ovalis, 

 sat convexus, testaceo-ferrugineus, elytris nigris testaceo-signatis, confertim 

 fortiter aequaliter puuctatus. Long. 3|, lat. 2^ m.m. 



Mas, trochanteribus anterioribus elongatis, subtus sinuatis ; tarsis anterioribus 

 et intermediis dilatatis. 



This species is very closely allied to Hyphydrus decem-maculatus, but is smaller, 

 and different in colour. The coxa? are more densely punctured, and the front tarsi 

 of the male are a little more dilated. I have seen but a single male of the species, 

 and have not been able to see exactly the form of the front trochanters. 



Australia. 157. 



3.58. Hyphydrus australis, Clk. M.C. — Oblongo-ovalis, sat latus et convexus, 

 nitidus, infra colore variabilis, supra rufo-testaceus, prothorace basi medio elytris- 

 que nigro- vel fusco-signatis, confertim, aequaliter fortiter punctatus, elytris stria 

 discoidali ad basin vix distincta, suturali subobsoleta. 



Mas, tarsis anterioribus fortiter dilatatis, subdeplanatis, articulo tertio quam 

 basali fere latiore ; intermediis subdilatatis, lateraliter compressis. Long. 5, lat. 

 3 m.m. 



Fern., pedibus minoribus, tarsis simplicibus. Long. 4^ m.m. 



Though the male of this species a good deal resembles the male of H. lyratus^ 

 the two species are found to be very distinct when the corresponding sexes of each 

 are compared together. The structure of the front tarsi in the male of the 

 present species is peculiar, the second joint is of an irregular, somewhat rhom- 

 boidal form, and when the soles are looked at it is seen that the posterior 

 portions of the second and third joints are on a different plane to the anterior 

 portions, and that only the anterior portions of these two joints are clothed 

 with tomentum. 



Australia, (apparently throughout), New Oaledouia. 47. 



I. 31.— Genus STERNOPRISCUS. 



Anterior and middle tarsi with the fourth joint distinctly visible between the 

 third and fifth joints. Mesosternum intervening in a conspicuous manner between 

 the pro- and metasternum, its epimera extremely short, almost linear; ventral seg- 

 ments not soldered with the coxse. Hind coxal cavities not contiguous but pro- 

 longed inwards over the coxal process, so as to become nearly connected by these 

 prolongations. 



