16 



Hydroscapha Crotchii. 



//. Crotchi, Sharp, Ent. Mo. Mag. xi. p 103, 1874 ; Matthews, Essay Gen. Hydros. 



p. 17, plate, 1876. 



L. c. abd. retracto, ^ lin. = 0-50 mm ; abd. extensn, ,';. lin. = 0-75 mm. — 

 Conica, vel postice truncata, vel valde elongafca, convexa, nitidissima, livido-brunnea, 

 pilis brevissimis pallidis sparsissime vestita; capite magno, lato, antice rotundato, 

 punctorum serie transversa impresso; pronoto brevi transverso, postice dilatato, 

 angulis sat acutis, leviter remoteque punctato ; - lytris longioribus, ovalibus ad apices 

 abrupte truncatis, ordinibus transversa Binuatis leviter asperatis; abdomine valde 

 attenuate, Begmentis quinque partim apertis; pedibus atque antennis pallidis, his 

 ad apices infuscatis. 



Boil ii coiiie, either truncate or elongate posteriorly, convex, very shining, livid 

 brown, sparingly clothed with very short pale hair. 



Head very large ami broad, alutaceous, Bhining, with a row of four punctures on 

 each side near the eye, clypeus divided from the vertex by a suture and row of 

 punctures. Eyes large, rounded. Antenna pale yellow, dusky towards the apex. 



Tkoraa rather short, transverse, broader but Bcarci 1\ Longer than the head, dilated 

 at the base, alutaceous, remotely punctured, Bides slightly rounded, basal 

 margin sinuated, with the angles acute. 



Scutellum moderate, acutely triangular. 



Elytra rather long, very convex, rather broader and more than one-half longer than 

 the head and thorax, widest before the middle, rather deeply asperate in trans- 

 verse rows, suture not elevated, extremities broad and truncate. 



Abdomen elongate, much attenuated, convex, with live segments exposed, basal 

 segment alutaceous and densely pubescent, black, tin- other segments dusky 

 castaneous, shining, remotelj punctured, apical segment long, with a divergent 

 longitudinal impression on each side near the middle, apical ventral segment 

 deeply emarginate at the apex, with a longitudinal impression in the middle 

 extending to the base. 



Legs moderate, pale yellow. 



Uiulif jiniis nigro-piceous, with the mouth, coxae, and epipleural folds of the 

 elytra pale. 



Differs from //. nataris in the smaller size, narrower and more cylindric form, 

 longer antennae, depressed suture, and sculpture of every part. 



Habitat, Europe. Found in the river Manzanares, in Spain, by .Mr. G. It. Crotch. 



