On Aquatic Carnivorous Colcoptera or Dytiscide. 459 
I have seen only a single individual, and although it is not in good condition, it 
appears to me to be certainly a distinct species. 
Syria, (Dr. Millingen). 1150. 
561. Dytiscus nigrita, Fab., Hydroporus mgrita, M.C_—Ovalis, latiusculus, minus 
convexus, breviter tenuius pubescens, minus nitidus vel opacus, niger vel piceus, 
antennis pedibusque rufis illis basi excepto plus minusve infuscatis ; prothorace 
medio punctis paucis minutis ; elytris minus crebre et fortiter punctatis, punctis 
versus apicem obsoletis; coxis posterioribus fortiter punctatis ; abdomine apice 
impunctato. Long. 3, lat. 13 m.m. 
This is a variable species in size and colour, and even somewhat in sculpture ; 
specimens occur in which there are to be seen a few distinct punctures on the last 
ventral segment, and these individuals are generally narrower and have darker legs 
and antennee, but intermediate specimens occur. I do not see any characters to 
distinguish the sexes. According to Sahlberg and Wehncke, Hydroporus 
subalpinus, Th. (No. 1,434, huj. op.), is not distinct froin this species, but I cannot 
myself give an opinion on the point. 7 
Europe, from Finland, (63° 40', Sahlberg), to the Guadarrama. 339. 
562. Hydroporus brevis, Sahl., M.C.—Breviter ovalis, sat latus et convexus, 
nitidus, breviter tenuius pubescens, niger, antennis pedibusque rufis ; prothorace 
disco punctis paucis sparsis, basi utrinque fortius punctato ; elytris sat crebre et 
fortiter punctatis ; coxis posterioribus fortiter punctatis; abdomine apice fere 
impunctato. Long. 23, lat. 13 m.m. 
The much smaller size, and the more shining surface should prevent this species 
from being mistaken for a variety of Dytiscus nigrita, Fab. I see no sexual 
characters. 
Europe. Apparently confined to the north, ascending in Lapland and Finland to 68° north. Arctic 
Siberia, (Jenisei), Sahlberg. 388. 
563. Hydroporus obscurus, Sturm., M.C.—Ovalis, minus latus, sat convexus, Vix 
nitidus, breviter tenuius pubescens, fusco-rufus, capite, antennarum basi pedibusque 
dilutioribus, pectore nigricante; prothorace medio late impunctato, basi sat 
evidenter punctato ; elytris sat fortiter minus crebre punctatis ; coxis posterioribus 
‘ 
fortiter punctatis ; abdomine apice haud punctato ; antennis brevibus. Lone. 25, 
lat. 13 m.m. 
I can see no sexual characters in this small but distinct species. 
Northern and central Europe, and Arctic Siberia; North America ; ascends in Finland to 68° north 
according to Sahlberg. Jenisei, Sahlberg. The North American habitat is given on the authority of 
two individuals from the late Andrew Murray’s collection. 387. 
TRANS. ROY. DUB. SOC., N.S., VOL. II. 30 
