On Aquatie Carnworous Coleoptera or Dytiscide. 259 
I. 1—Genus PHLOBIUS. 
Posterior coxze separated from the metasternum by a suture which extends 
directly outwards, not at all forwards ; metasternum in the middle behind with a 
piece marked off by a distinct suture ; swimming legs slender, but with long ciliz, 
their tarsi elongate and slender ; prosternal process, elongate, bluntly acuminate 
at the tip. | 
This genus comprises only three species, one of them European, the others 
Australian ; the European species, has the scutellum quite exposed, but in those 
from Australia this part is nearly covered by a prolongation of the base of the 
prothorax. 
1. Dytiscus tardus, Herbst. Hydrachna tarda, M.C.*—Convexus, sine 
pubescentia fere opacus, ferrugineus, capite utrinque, prothoraceque anterius et 
posterius nigricantibus, elytris fuscis, marginibus irregulariter late dilutioribus, 
corpore subtus ex parte nigro, antennis pedibusque testaceis: prothorace basi et 
apice elytrisque punctato-rugulosis; corpore subtus dense subtilissime punctato. 
Long. 10, lat. 6 m.m. 
The male has the three basal joints of the front and middle tarsi a good deal 
dilated, and furnished on the under side with tomentum, the dilated joints are a 
good deal compressed at the sides. 
Central and Southern Europe, Corsica and Algeria; common in isolated spots. Not found in 
Scotland, Denmark, Finland or Scandinavia. 235. + 
2. Pelobius australasiz, Clark. Hydrachna Australasie, M.C.— Convexus, 
sine pubescentia, sat nitidus, niger, thorace, elytris, antennis pedibusque ferrugineis; 
prothorace dense subtiliter, aqualiter punctato, elytris dense subtiliterque punctato- 
rugulosis ; corpore subtus fortiter punctato. Long. 10, lat. 6 m.m. 
In the male the basal joints of the front and middle tarsi are slightly dilated 
and are furnished beneath with tomentum. 
Australia, (Melbourne). 236. 
The two Australians differ from D. tardus, by the small scutellum and obsolete frontal suture. 
*The name followed by the letters M.C. is that under which the species is recorded in the Munich 
Catalogue of Coleoptera (Catalogus Coleopterorum, autoribus Dr. Gemminger et B. de Harold, Tom. II. 
Monachii, 1868). Such specific names as are not recorded in the Munich Catalogue will be accompanied 
by a reference to the actual work in which the original description appeared. Both these references are 
absent in the case of species here named and characterised for the first time. 
} The number placed in this position is that which I have used for labelling specimens and collections 
submitted to me for determination during the progress of the work. It may therefore be quite disregarded 
except by those who have from me specimens bearing these numbers. 
TRANS. ROY. DUB. SOC., N.S. VOL. II. 2M 
