On Aquatic Carnivorous Coleoptera or DytiscidcB. 737 



Group 5. 



1152. Cybister wehnckianus, n. sp. — Minor, ovalis, fere angustus, parum nitidus, 

 supra nigricans, capite anterius prothoraceque ad latera testaceis ; elytris vitta 

 submarginali angusta ante apicem omnino obsoletescente testacea, epipleuris 

 nigricantibus ; subtus piceus, coxis posterioribus externe vage testaceo-maculatis, 

 metasterno anterius subprominulo, laciniis impressis, pedibus quatuor anterioribus 

 testaceis, femoribus in medio tibiisque intermediis obscurioribus, pedibus posteriori- 

 bus nigricantibus ; elytris transversim rugosulis, epipleuris versus apicem latis. 

 Long. 20, lat. 11 m.m. 



I have not seen the male of this species ; the elytra has on the basal portion of 

 the elytra rather numerous short irregular scratches, which do not reach either to 

 the suture or lateral margin, and, becoming very obscure as they extend backwards, 

 cease entirely about half way to the apex : the thorax is almost free from sexual 

 sculpture, although its surface is uneven ; on careful examination however traces 

 of excessively fine short scratches may be detected along its basal portion. 



This species seems allied to the preceding one although very distinct therefrom ; 

 the gibbosity of the anterior part of the metasternum is indistinct, but the coarse 

 series of punctures, and the impressions on its lacinise are much the same ; the 

 colour of the epipleurse of itself renders the two species very distinct. 



India (^). 1083. 



1153. Cybister cephalotes, n. sp. — Ovalis, sat latus, antei'ius parum angustatus, 

 capite majore ; supra olivaceus, capite anterius prothoraceque ad latera testaceis, 

 elytris vitta Integra determinata laterali cum epipleuris testaceis, his externe nigro- 

 lineatis ; subtus niger ; pedibus anterioribus et intermediis rufis, nigro-variis, 

 posterioribus nigricantibus; prothorace ad latera subimpresso. Long. 28, lat. 

 14 m.m. 



The male has the front tarsi rather small, and their pubescent area is small ; on 

 the middle tarsi the two intermediate joints bear moderately long sexual hairs, and 

 there is a very slight development of sexual pubescence on the folio wing joint : the 

 female has a patch of peculiar sexual sculpture along the middle of the wing-case but 

 not reaching the base ; this sculpture consists of very short, deep, punctiform im- 

 pressions, mixed with which are some short angular or curved impressions and 

 numerous fine punctures, but extends only over a small space and is widely 

 separated both from the suture and lateral margin. 



This species is a peculiar one, bearing a considerable resemblance to Dytiscus 

 tripunctatus{No. 1140), but has the head larger, and the thorax with a sort of 

 impression along the side ; the form of the yellow band along the elytra is quite as 

 in D. tripunctatus, but the epipleurse externally are margined with dark colour ; 



