On Aquatic Carmvorous Coleoptera or Dytiscide. 733 
The male anterior tarsi are small; and on the intermediate feet the three basal 
joints are furnished beneath with rather short sexual pubescence, the patch on the 
basal joint is broad, that on the third joint quite narrow, the one on the second 
joint being intermediate in width. The female has no trace of any sexual sculp- 
ture. 
The species is readily distinguished amongst its allies by its small size: it varies 
somewhat in form; some individuals being notably more elongate than others, it 
also varies somewhat in the colour of the undersurface, this being sometimes nearly 
black, more rarely piceous red. 
Algeria, Senegal, Madagascar. 1076. 
1146. Cybister occidentalis, Aubé, Trogus occidentalis, M. C_—lLatus, ovalis, 
parum convexus, nitidus, niger, parum olivaceus, capite anterius prothoraceque ad 
latera testaceis, elytris margine externo (cum epipleuris) late testaceo; pedibus 
anterioribus rufis, femoribus fusco-maculatis, intermedius piceis, femoribus basi 
apiceque rufescentibus, posterioribus nigricantibus, femoribus angulo externo 
posteriore recto: antennis rufis; elytrorum epipleuris versus apicem sat latis et 
planatis. Long. 33, lat. 19 m.m. 
The male has the front tarsi rather large in the transverse direction; the 
intermediate feet bear patches of moderately short sexual pubescence, on the 
three basal joints, the basal patch is broader than the others, that on the third joint 
being quite narrow, the claws are rather long and stout, curved and distinctly 
unequal ; in the hollow just in front of the articulation of the swimming legs there 
are four or five coarse, short, raised ridges. The female has a well marked sexual 
sculpture on the wing-cases and thorax; on the former there are fine scratches of 
variable length, some of them elongate, they are directed in the long axis of the 
body and show a tendency to converge or anastomose here and there, at the base 
they extend from the scutellum to the shoulder, elsewhere they reach neither to 
the suture nor to the lateral margin although they invade the inner portion of the 
yellow band ; they reach about four-fifths of the way to the apex ; on the thorax the 
scratches are short, and not numerous, they are also absent altogether from the disc ; 
on the head there are some fine scratches behind the eye. 
In this as in the following species, the yellow band at the apex of the elytra 
does not terminate in quite a point at the suture, so that it is distinctly connected 
with that on the other wing-case. 
I have seen specimens of this species in more than one collection, said to be from 
MonteVideo and Buenos Ayres, but I believe erroneously. 
Cuba. 1077. 
5 B2 
