On Aquatic Carnicorous Cokoptera or DytisidcB. 557 



794. llybius limbatus, n. sp. — Minor, ovalis, sat convexus, tsubnitidus, testaceus, 

 supra seneus, capite thoraceque plurf minusve pallescentibus, clytris margine lato 

 testaceo ad apicem obsoletescente, dense punctato-reticulatis ; coxis posterioribus 

 fere esculpturatis, marginu anteriore extus abrupte deflexo ; prosterni proctssu 

 apice brevi. Long. 8, lat. 41 m.m. 



The male has the middle tarsi with the basal joints a little incrassate, and 

 furnished beneath with moderately long hairs bearing minute palettes; on the hind 

 feet the outer claw is considerably shorter than the inner one and has an acuminate 

 extremity ; the apical ventral segment bears no carina, and has the hind margin 

 somewhat obsoletely Tugose : the only individual I have seen of this sex has lost 

 its front feet. The female has the last ventral segment almost simple. 



Eikstem Siberia. 83 -t. 



Gnoup 2. 



795. llybius discedens, n. sp. — Ovalis, angustulus, sat convexus, sat nitidus, 

 niger, antennis pedibusque anterioribus rufis, pedibus posterioribus piceis ; elytris 

 ad basin densius parum perspiciie punctato-reticulatis. ad apicem j^unctulatis, 

 punctis subseriatis conspicuis ; coxis posterioribus fere laevigatis ; prosterni processu 

 satelongato; tarsis posterioribus articuHs tantum breviter lobatis. Long. Th-Sl 

 m.m. lat. 4-4| m.m. 



The male has the front and middle tarsi almost simple and unincrassate ; the 

 claws of the front feet are rather short, equal in length, the anterior rather 

 dilated, with its lower edge nearly straight, the hinder one rather more slender, 

 and with its basal portion distinctly emarginate beneath. The apical ventral seg- 

 ment has its hinder part thin in the middle and smooth, but with some coarse striae 

 on each side, its hind margin truncate or rather emarginate truncate : in the female 

 this segment has a strong very short plica, and the appearance of a deep narrow 

 notch at its apex. The claws (jf the hind feet are nearly similar in the two sexes, 

 they are comparatively little unequal, still the outer is a good deal shorter than 

 the inner, they are both rather slender and acuminate, and the outer one has its 

 apex more curved than the other has, this is especially conspicuous in the female, 

 the apical portion of the outer claw being in it strongly curved. 



The species is scarcely so large as I. guttiger, to Av^hich it has at first sight a 

 resemblance : indeed superficially it suggests itself as a connecting link between 

 Agabus and the smaller black Ilybii; it has a lateral and an apical yellow mark on 

 each wing case; the hind coxce are not very large, and yet their front border is not 

 very widely separated from the middle coxse. The swimming legs are feeble (for 

 its genus) and tlie group of seta; on the femoral angle is very ill developed. 



North Anifriou, (Hudson's l>:iy). 'J'iO. 



4 C » 



