On Aquatic Carnivorous Coleoptera or Dytiscide. 739 
intermediate tarsi; 1t has too the prosternum with its anterior front angle much 
rounded off, whereas it 1s prominent and robust in Cybister buqueti. 
Madagascar. 1086. 
1156. Cybister confusus, n. sp.—Major, ovalis, niger, capite anterius prothorace- 
que ad latera testaceis, elytris vitta intramarginali (apice parum hamato-dilatata), 
suturam attingente testucea; corpore subtus nigricante, pedibus anterioribus et 
intermediis rufis, his tibiis infuscatis. Long. 36, lat. 193 m.m. 
In the male the front tarsi are large, attaining 4 m.m. in the transverse direction ; 
the intermediate tars: 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 cedeagus 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 well 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 epipleure 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 segment. 
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 epipleurze 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., Zrogus limbatus, M.C.—Major, ovalis, supra 
olivaceo-niger, capite anterius prothoraceque ad latera testaceis, elytris vitta intra- 
marginali testacea, apice argute hamato-dilatata, suturam haud attingente ; corpore 
subtus nigricante, pedibus anterioribus et intermediis rufis, his tibiis mfuscatis, 
Long. 34, lat. 192 m.m. 
TRANS. ROY, DUB. SOC., N.S., VOL. II, 
