632 On Aquatic Carnivorous Coleoptera or Dytiscide, 
and the fourth joint more clongate than on the front feet. There is no difference 
in the sculpture of the sexes. 
The species varies but little, and is readily distinguished by the peculiar sculpture 
of the wing-cases which are covered with curved transverse impressions, having 
very much the appearance of scales. 
Southern Europe, Northern Africa, Canary Islands, (C. Verde Islands?). (Southern France, Spain, 
Portugal, Sardinia, Sicily). 925. 
979. Dytiscus lanio, Fab., Scutopterus lanio, M.C.—Oblongo-ovalis, parum con- 
vexus, nitidus, piceo-niger, prosterno piceo, antennis, palpis, pedibus anterioribus, 
capite anterius, vertice maculis transversis prothoracisque lateribus rufis, elytris 
brunneo-testaceis, creberrime nigro-irroratis, prothorace opaco, profundius irregu- 
lariter reticulato ; elytris nitidis, obsolete tuberculatis, punctis seriatis conspicuis. 
Long. 22, lat. 102 m.m. 
The male characters are quite the same as in the preceding species, and there is 
no sexual difference of sculpture: it is probable however that the sculpture of the 
wing cases in the female is variable, for in Aubé’s type of that sex the elytra bear 
on their anterior portion curved impressions, approximating to what exists in 
Meladema coriacea. Scutopterus imbricatus, Woll. Tr. Ent. Soc. 1871, p. 220, (No 
1,505 huj. op.) is apparently a closely allied species from the same locality. 
Madeira. (? North Africa). 926. 
II. 12.—Group Dyriscrnt. 
Abdominal stigma of last two segments enlarged, that on the penuitimate seg- 
ment being at least, 1 m.m. in diameter, or more than one-third of the half-width 
of the dorsal aspect of the segment. Stigmatic rugze on side piece of first ventral 
seoment highly developed. Swimming legs rather slender, terminated by two 
nearly equal claws. Outline of eye not emarginate at inner edge. Male anterior 
tarsi with the three basal joints dilated and coadapted to form a nearly circular 
plate. 
Only two genera are comprised in this group; they may be very readily distin- 
guished as follows :— 
Elytra with a lateral yellow stripe. DYTISCUS. (Vide p. 634.) 
Elytra without a lateral yellow stripe. HYDERODES. (Vide p. 633.) 
