On Aquatic Carnivorous Coleoptera or DytiscidcB. 739 



intermediate tarsi ; it has too the presternum with its anterior front ano-le much 

 rounded off, whereas it is prominent and robust in Cybister bnqueti. 



Madagascar. 1086. 



1156. Cybister confusus, n. sp. — Major, ovahs, niger, capite anterius prothorace- 

 que ad latera testaceis, elytris vitta intramarginah (apice parum hamato-dilatata), 

 suturam attingente testacea; corpore subtus nigricante, pedibus anterioribus et 

 intermediis rufis, liis tibiis infuscatis. Long. 36, lat. 192 m.m. 



In the male the front tarsi are large, attaining 4 m.m. in the transverse direction ; 

 the intermediate tarsi have on each of the two basal joints a very large broad patch 

 of quite short sexual pubescence, and there may generally be seen a line of rudi- 

 mentary pubescence on the third joint, their claws are rather long, the outer one is 

 thick and but little curved till near the apex when it takes a sudden bend, the inner 

 one is shorter and much thinner. The oedeagus has the inferior lobe with its 

 apical part oblong in form, (becoming however just slightly broader towards the 

 extremity), and its apex shows a deep ^vell marked notch ; the dorsal lobe termi- 

 nates in two contiguous processes, which reach as far as the apical notch, they are 

 flattened and roughened near the apex which is minutely turned upwards. The 

 female has a very highly developed sexual sculpture, the thorax being covered with 

 short, curved, or angular, irregularly directed scratches; these scratches entirely 

 cover the thorax (except the front margin) though they are usually finer about the 

 middle than at the sides ; the epipleurfe of the elytra are flattened and obliquely 

 horizontal, but not very broad, the obliquity commences very near the base, and 

 ceases in a gradual manner at about the hind margin of the second ventral seo-ment. 

 Although this species is excessively similar to the following one and universally 

 mixed with it in collections, it is nevertheless perfectly distinct, the form of the 

 cedeagus in the male being characteristic and quite constant ; while the female has 

 the epipleurte in their flattened part less broad. As smaller characters, it may be 

 mentioned that the form of this species is usually flatter with the outline less curved 

 at the sides, and with the yellow band of the elytra not forming a well marked hook 

 near the apex, and nearly or quite attaining the suture; while the female has the 

 sexual sculpture less absent along the mesial line of the body. 



India, Ceylon, China, (this latter locality somewhat doubtful). 1087. 



1157. Dytiscus limbatus, Fab., Tragus limhatus, M.C. — Major, ovalis, supra 

 olivaceo-niger, capite anterius prothoraceque ad latera testaceis, elytris vitta intra- 

 marginali testacea, apice argute hamato-dilatata, suturam hand attingente ; corpore 

 subtus nigricante, pedibus anterioribus et intermediis rufis, his tibiis infuscatis. 

 Long. 34, lat. 19* m.m. 



o 



TKANS. EOY, DUB. SOC, N.S., VOL. II 



