On Aquatic Carnivorous Coleoptera or, Dytiscide. 415 
440. Hydroporus dispar, Germ., M.C.—Ovalis, brevissime pubescens, densissime 
punctatus, opacus, nigricans, antennis, pedibus, capite, thorace elytrisque testaceis, 
thorace medio latius infuscato, elytris lineis undique confluentibus obscuratis; 
corpore subtus densissime punctato. Long. 4%, lat. 2} m.m. 
In the male the front and middle tarsi are broad, and the front tibize are 
extremely thick, and have a very large excision in the middle inwardly : the middle 
tibize are a little curved. The front tarsi of the female are elongate and slender. 
Australia, (Adelaide). 434. 
441. Hydroporus wollastoni, Clk., M.C.—Ovalis, brevissime pubescens, densis 
sime punctatus, subopacus, ferrugineo-testaceus, antennis, pedibus, capite thorace- 
que testaceis, elytris lineis plurimis nigris, ad latera et inter lineas primam et 
secundam maculis interjectis; corpore subtus densissime punctato, opaco ; tarsis 
anterioribus et intermedius elongatis. Long. 44, lat. 23 m.m. 
In the male the front and middle tarsi are broad ; the front tibize are moderately 
broad, but their lower part is not thick, so that the notch on the inner edge 
appears to make only a shallow excision: the middle tibize are a little curved. In 
the female the thorax forms a more continuous line with the elytra than it does in 
the male, the surface is duller, and the front and middle tarsi are slender. 
Though the species varies a good deal, I have not quite been able to connect H. 
undecimlineatus, (No. 439), with it. 
Australia. 435. 
442. Necterosoma regulare, n. sp.—Ovalis, brevior, convexus, omnium brevissime 
pubescens, subopacus, densissime, sat subtiliter ruguloso-punctatus, testaceus, pectore 
abdomineque fuscis, thorace anterius et posterius elytrisque lineis latis higris ; 
corpore subtus densissime punctato, coxis fortiter rugulosis ; prothorace lateribus 
ante medium obsoletissime angulatis. Long. 3#, lat. 25 m.m. 
The male at first sight differs but little from the female; it has however the 
front and middle tarsi slightly broader, and the front tibie have a slight 
emargination near the extremity, the middle tibiz also have their lower portion 
somewhat excised. 
Australia, (Port Denison, and North West Australia). 436. 
443, Necterosoma arcuatum, n. sp.—Ovalis, brevior, sat convexus vix pubescens, 
opacus, densissime sat subtiliter ruguloso-punctatus, ferrugineus, prothorace 
anterius et posterius nigro, elytris lineis nigris ; corpore subtus densissime punctato, 
coxis sat fortiter rugulosis. Long. 33, lat. 2 m.m. 
