On Aquatic Carnivorous Cohoptera or Dytiscidce. 549 



sublaevigatis, versus apicem dense minuteque rugosis ; prosterni processu lato, 

 utrinque longitudinaliter depresso, apice acuminato. Long. 8, lat. 4| m.m. 



The male has the front and middle tarsi a little incrassate, and the three basal 

 joints provided on rather a large space with glandular hairs ; the hinder claw on 

 the front feet is a little shorter and thicker than the anterior one. Although the species 

 is very variable in its sculpture, there seems to be no sexual disparity in this 

 respect. It is not easy to find two individuals exactly similar in colour ; and 

 the variations of size and sculpture are also very great. The largest individuals I 

 have seen are from Piedmont, and are extremely smooth and shining, the elytra 

 appearing in fact almost free from sculpture : the smallest individuals are those 

 found in Scotland, and in them the sculpture of the wing cases is (comparatively) 

 deep, and the surface dull ; and in this same variety the yellow markings of the 

 elytra are reduced to the marginal band. In the mountains of Spain, a variety (A. 

 graellsi, Har.) is found having the sculpture dense and deep, and the yellow marks 

 on the elytra forming two or three pale spots on each. All the variations are found, 

 when an extensive series is examined, to be connected together in the most intimate 

 and complicated manner. 



Europe. (North America'?) ; (Sweden; Finland to 68° 30' North, Sahlberg ; Britain; France; Spain; 

 Piedmont ; Germany). 834. 



779. Agabus sinuatus, Aubd, M.C. — Ovalis, statura coloreque variabilis, ferru- 

 gineus, vertice, prothorace elytrisque variabiliter infuscatis, (vel subsenescentibus), 

 his ad basin et ad marginem exteriorem anterius plus minusve testaceo-signatis ; 

 corpore supra punctis impressis, crebribus, conspicuis, praetereaque plus minusve 

 minute ruguloso, rugulositate hac ver.sus elytrorum apicem profunda et densissima ; 

 prosterni processu lato, piano, tenuiter marginato, hand impresso, apice acuminato. 

 Long. 82, lat. 4f m.m. 



The three basal joints of the front and middle tarsi are in the male very little 

 incrassate, but they are furnished beneath with moderately long glandular hairs ; 

 the front claws are equal, if there be a difference the hinder one is slightly more 

 slender than the front one. 



This species seems to be almost as variable as Dytiscus maculatus, but may be 

 readily distinguished by the presence of a conspicuous true punctuation on the 

 upper surface, and by the finely margined, unimpressed prosternal process. 



Syria, Caucasus, Asia Minor, Northern Persia. 835. 



780. Agabus pictipennis, Sharp, Tr. Ent. Soc. Lond. 1873, p. 49. — Ovalis, sub- 

 depressus, pernitidus, sublsevigatus, colore variabilis, ferrugineus, capite et thorace 

 plus minusve infuscatis, elytris fuscis, fascia basali maculisque sublateralibus testaceis ; 

 prothorace baud brevi, angulis posterioribus subacutis ; elytris omnium obsoletissime 



4 B 2 



