518 On Aquatic Carnivorous Coleoptera or Dytiscidce. 



According to Professor Sahlberg this is the species Matinerheim intended to call 

 A. adjiressus, but is not the one described by Aube under that name, (vide No. 719). 



Dauria. 726. 



719. Agabus adpressus, Aube, M.C. — Oblongo-ovalis, niger, nitidus, supra 

 ainescens, clypeo rufescente, antennis pedibusque rufis ; prothorace lateribus sat 

 rotundatis, angulis posterioribus obtusis. Long. 7, lat. 3f m.m. 



There is a difterence in the sculj^ture of the sexes, the female having the elytra 

 extremely finely reticulate, while in the male the reticulation is so obsolete as to 

 easily escape detection : the male has the basal joints of the front and middle tarsi 

 a little incrassate, and furnished beneath with glandular hairs, and the claws of 

 the front feet are elongate and slightly sinuate beneath. The prosternal process 

 in this species is not broad, and is but little compressed laterally, and is feebly 

 punctulate at the sides, the metasternal cavity is rather short and narrow. The 

 species is closely allied to Agabus sahlbergi, but is smaller, and the prosternal 

 process is rather shorter flatter and more punctate, and the sides of the thorax are 

 more contracted at the hind angles. 



Arctic Siberia, (Dudinka, J. Sahlberg). 738. 



Group 12. 



Prosternal process small, much compressed ; middle legs very approximate so that 

 the metasternal groove between these is o^udimentary and obscure. Sides oj thorax 

 rounded. Coxal lines rather deep and a good deal divergent in front. 



Four species from both Old and New Worlds. 



720. Dytiscus wasastjernse, Sahl., Agabus Wasastjernce, M.C. — Oblongo-ovalis, 

 niger, supra subsenescens, sat nitidus, antennis pedibusque rufis; prothorace 

 lateribus rotundatis, angulis posterioribus rotundato-obtusis, margine laterali baud 

 crasso; elytris dense evidenter reticulatis et punctulati-^. Long. 7, lat. 4 m.m. 



The sexes are vei7 similar ; in the male the three basal joints of the front and 

 middle tarsi are scarcely incrassate but are furnished beneath with glandular haii'S. 

 The apical joints of the antennae in this species are rather more elongate and slender 

 than in the allies. 



Northern Europe; (Sweden, and Finland). 739. 



