On Aquatic Carnworous Coleoptera or Dytiscide. 645 
The palettes of the male tarsi are moderately developed, and show no 
difference from what exists in D. circumeinctus. The species is nearly always of 
more slender form aud of a greener colour than the other allies of Dytiscus margin- 
alis, and is readily identified by the great elongation of the coxal processes. It 
varies a good deal in colour, size and width ; the specimens from the northern part 
of its area of distribution being generally broader and ofa less green colour than 
most of the individuals which are found in southern Spain and Algeria; in the 
suleate female of the larger variety the grooves are generally continued rather 
nearer to the extremity of the wing-cases. In the north it would seem that sulcate 
females are more abundant than smooth ones, while in the south the reverse is 
the case. 
Central and Southern Europe; apparently most common in the neighbourhood of the Mediterranean 
Sea Corsica, Algeria; (England, France, Germany, Spain, Corfu, Hungary). 950. 
1002. Dytiscus lapponicus, Gyll., M.C.—Subtus testaceus, abdominis lateribus 
nigro-maculatis, supra piceus, prothorace limbo omni late flavo-marginato, scutello 
flavescente, elytris lateribus lineisque tenuibus flavis ; antennis pedibusque testaceis ; 
prosterni processu brevi; coxarum processubus apicibus distantibus, subito angus- 
tatis, elongatis et acuminatis. Long. 27, lat. 132 m.m. 
Mas, nitidus, elytris ad apicem fortiter punctatis. 
Fem. (a), opaca, elytris ad basin ultra medium suleatis, ad apicem fortiter 
crebrius punctatis ; prothorace undique creberrime punctato. 
(b), nitida, prothorace subopaca, preesertim in medio crebrius subtiliusque 
punctato, elytris ad apicem fortiter punctatis. 
The male has the smali palettes of the tarsi moderately developed. 
The species has the outline of the thorax and elytra more discontinuous than in 
any other species, the thorax being narrower than usual especially at the base ; the 
eyes are always largely bordered with yellow : the contraction of the coxal processes 
takes place on their inner edge just below the coxal notch: the anterior border of 
the hind coxa approaches nearer to the middle coxa than in any other species, and 
the terminal portion of the epipleuree is a little broader than in the other species of 
the D. marginalis group. These characters allow the species to be easily recognized, 
although it is a very variable one in size and colour. The yellow irregular lines 
on the elytra can sometimes scarcely be detected ; at other times the yellow colour 
is more than usually predominant, and the black mark on the middle of the thorax 
may even be broken up: very rarely the elytra are of a greenish olivaceus cr rather 
of a piceous colour. The specimens from Northern Germany are larger and darker 
than any others I have seen. 
I am not quite certain that the individual, the only one I have seen, from Siberia 
£ O 2 
