On Aquatic Carnworous Coleoptera or Dytiscide. “lal 
anterioribus rufis, tarsis intermediis piceis, pedibus posterioribus nigricantibus ; 
elytrorum epipleuris versus apicem parum latioribus. Long. 30, lat. 18 m.m. 
In the male the front tarsi are small, attaining about 23 m.m. in the transverse 
direction, their claws are rather short; the middle teet have elongate sexual 
pubescence on the three basal joints, their claws are of moderate size and simply 
curved, the inner one being a good deal shorter than the outer. The female I have 
not seen. 
The species much resembles Cybister costalis (No. 1116), but is smaller and 
narrower, and the male anterior tarsi are smaller, and the claws of the intermediate 
feet much less developed, and the epipleurz of the elytra are much narrower. It 
is smaller than C. robustus, and has the epipleurze narrower. 
Panama. 1108. 
1113. Cybister robustus, Aubé, Trogus robustus, M.C.—Ovalis, latus, anterius 
angustatus, sat convexus, nigricans, capite anterius prothoraceque ad latera tes- 
taceis, elytris vitta intramarginali, ad apicem lata sed parum determinata, testacea ; 
pedibus quatuor anterioribus rufis, tarsis intermediis piceis; pedibus posterioribus 
piceis, tibiis superne rufescentibus, femoribus nigris; elytrorum epipleuris sat latis. 
Long. 35, lat. 20 m.m. 
I have seen only one male of this species; the sexual characters of that sex 
seem to be the same as in M. obesus, the front tarsi being scarcely 24 m.m. in the 
transverse direction. 
South America. (Buenos Ayres, fide Castlenau). 1109. 
1114. Megadytes perplexus, n. sp.-—Ovalis, latus, anterius angustatus, convexus, 
supra olivaceo-niger, capite anterius prothoraceque ad latera testaceis, elytris vitta 
intramarginali ad apicem obsoletescente testacea ; subtus niger, pedibus quatuor 
anterioribus rufis, tarsis mtermediis piceis; pedibus posterioribus piceis, tibiis 
superne rufescentibus, femoribus nigris; elytris ad apicem punctis impressis con- 
spicuis, epipleuris parum latis. Long. 35, lat. 20 m.m. 
The characters of the male are the same as in Cybister robustus; the species 
must indeed be very closely allied to C. robustus, but the only individual before 
me I cannot reconcile therewith ; it differs somewhat in colour and form, and has 
the epipleurze decidedly narrower throughout its whole length. It is perhaps still 
closer to M. obesus, but is considerably larger : in both these species the impressed 
punctures on the apex of the elytra are much more conspicuous than in the allied 
species. 
The only individual I have seen of this species existed in Edwin Brown’s 
collection, without any indication of locality. 
South America? 1110. 
