On Aquatic Carnivorous Coleoptera or Dytiscide. 719 
pubescence on the basal joint of the intermediate tarsi is also less obsolete. From 
C. siamensis, it differs by its smoother surface, and by the larger male tarsi ; while 
from C. convexus, it differs by its comparatively broader form which is more 
narrowed in front, and by its upper surface being less convex in the transverse 
direction, and by the male tarsi being rather larger. 
East India. 1057. 
1128. Cybister brevis, Aubé, Trogus brevis, M.C.—Ovalis, latus, anterius angus- 
tatus, supra olivaceo-niger, clypeo anterius vage irregulariter testaceo, subtus niger, 
antennis rufis extrorsum fuscescentibus, pedibus nigris rufo-variis ; capite crebre et 
fortiter, thorace sparsim subtilius, punctato. Long. 22, lat. 124 m.m. 
The front tarsi of the male are rather small, and the band of sexual pubescence 
on the basal joint of the intermediate tarsus is only very slightly developed ; the 
female shows no peculiar sexual sculpture. 
The peculiar punctuation of the head renders this species unmistakable ; except 
for that character it is allied to C. siamensis, but it is smaller, has the elytra 
smoother, and their epipleurze not so broad and flat in their posterior portion. The 
yellow mark on the front of the clypeus consists of an angular mark on each side, 
the two being connected together by a very short middle portion. 
Japan. 1058. 
1129. Cybister filicornis, n. sp.—Parvus, ovalis, latiusculus, anterius fortiter 
angustatus, supra parum convexus, niger, clypeo anterius prothoracisque lateribus 
testaceis, pedibus anterioribus et intermediis rufis, femoribus basin versus fuscis ; 
pedibus posterioribus piceis ; antennis rufis, extrorsum fuscis, elytrorum epipleuris 
versus apicem latis, et planatis. Long. 172, lat. 10 m.m. 
The anterior tarsi of the male are small, and the basal joint shows beneath a 
shining space instead of the usual pubescent area ; the basal joint of the intermediate 
tarsus shows beneath a linear band of short sexual pubescence, and there is a very 
slight development of similar pubescence at the extreme base of the second joint : 
the female has no sexual sculpture. 
This peculiar little species bears a great resemblance to small specimens of the 
American Dytiscus levigatus (No. 1106), but the male has only one claw on the 
hind tarsus, and the female has no trace of sexual sculpture : it cannot be mistaken 
for any other. 
According to the few specimens before me it varies somewhat in size and colour ; 
a variety from Portuguese Guinea, is smaller than the specimens from the Gaboon, 
has the upper surface more olivaceous, and the yellow band on the sides of the 
thorax broader. 
