632 Oil Aquatic Carnivorous Coleoptera or Dytiscidce. 



and the fourth joint more elongate 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 aie covered with curved transverse impressions, having 

 very much the appearance of scales. 



Southei-n Europe, Noitlieni Africa, Canary Islands, (C. Verde Islands'!). (Soiitliem France, Spain, 

 Portugal, Sardinia, Sicily). 925. 



979. Dytiscus lanio, Fab., Scutoptevus 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, jirofundius irregu- 

 lariter reticulato ; elytris nitidis, obsolete tuberculatis, punctis seriatis conspicuis. 

 Long. 22, lat. lOl 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 sculptui'e of the 

 wing cases in the female is variable, for in Aube'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. ( 1 North Africa). 926. 



II. 12. — Group Dytiscini. 



Abdominal stigma of last two segments enlarged, that on the penultimate 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 rugse on side piece of first ventral 

 segment 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- 

 tfuished as follows : — 



Elytra with a lateral yellow stripe. DYTISCUS. {Vide p. 634.) 



Elytra without a lateral yellow stripe. HYDERODES. ( Vide p. 633.) 



