A'jahuS.] ADEPIIAGA. 193 



sliire, Askliara Bopf ; Netlcy ; XorfoUc ; Cainbriilg'o ; NortliuinbL'rliiud district ; Scot- 

 laud, not common. Lowlands, Tweod, Forth, Solway, Clyde. 



Vroni A. fcm<ira/i.<i and A. uliginosns these species may be suporficially 

 ilistiiiguishcd by not having tlio margins of tliorax and elytra ligliter. 



Gronp rX. 



Tlind coxcc moderate, or rather large ; wings of metasternum moderate ; 

 prusternal process acuminate, finely margined ; swimming legs rather 

 stout ; elytra marked with yellow. 



A. didymus, 01. [n'freus, ]*ayk.). Oval, rather convex, broad and 

 robust, rather shining, almost smooth, upper side bronze, with the edges 

 of thorax and epipleuraa of elytra reddish; elytra with a waved testaceous 

 mark near the side just behind middle formed by the junction of two 

 spots which are very rarely separated, and another pale spot near apex, 

 which are both conspicuous and at once distinguish the species ; an- 

 tennae testaceous, legs pitchy-red ; male with the front and middle tai-si 

 distinctly thickened. Long. 8, lat. 4| mm. 



Kunning water; local, but widely distributed; London district; Xow Forest; 

 Dartmoor ; Swansea; Cambridge; Rcpton and other nuiilaud localities; liridlinjjton, 

 Yi):k>liii'e; Nortlunnberland district ; becomes rarer in the north of England, and lias 

 not been recorded from Scotland. 



Group X. 



Anterior tarsi of male never much thickened, their claws more or less 

 elongate, their under surface bearing distinct but not large palettes ; 

 prosternal process elongate, never broad, not keeled ; wings of meta- 

 sternum rather large. 



A. cong-ener, I'ayk. Oval or oblong oval, feubly convex ; head and 

 thoi'ax black, sometimes with labrum, two spots on vertex of head, and 

 sid(! margins of thorax leddish ; elytra fuscous, fuscous-red, or reddish 

 with the sides and base usually lighter ; antennae and legs I'ed, femora 

 darker; prosternal process long, narrow, acuminate, and impunctate ; 

 male with elytra bearing only obscure traces of reticulation, female with 

 sculpture varying from that of male to an extremely dense and distinct 

 reticulation which makes the whole surface ajjpear opaque ; colour of 

 elytra also very variable. Long. 7, lat. 4 mm. 



This appears to be essentially a northern, alpine <ir snbalpine species ; it has been 

 recorded Ironi Suflblk, Norfoll;, and near London, and also from Askbani Holt, York, 

 but all these localities rc(|uir(! coiitiiniatioii ; Nortliumberland district, " taken near 

 the top of Cheviot by Mr. .1. Hardy"; Scotland, abundant in mossy pools in higii 

 ilistricts ; Tweed, Tay, Dee, and Soiway. 



A. nebulOBus, Forst. {hipundatm, F.). Oval, rather depressed, 

 shiny, underside black; head black Avith mouth, cl3'peus, and two 

 spots on vertex more or less plainly testaceous ; thorax testaceous with 

 two more or less distinct, occasionally obsolete, dark spots on disc • 

 elytra testaceous with irregular variegated dark mirkings ; logs, iucludin" 



o 



