April, 1S4 1.] 27 



thorax black, with the lateral margins and a transverse middle line, testaceous- 

 yellow, middle line confluent with the lateral margins: elytra black, lateral 

 margins and a common narrow fascia immediately behind the base, testaceous, 

 fascia not confluent with lateral margins : three rows of remote impressed punc- 

 tures : posterior fed. and body beneath dull reddish-brown; intermediate and 

 anterior feet, testaceous : pleurx and epipleurx similarly colored. 



Hydaticus, Leach. 



H. meridionalis. Black; clypeus, lateral margins of the thorax, sides of the 

 elytra and a fascia behind the base, rufo-testaceous ; beneath black. — 6 1. long, 

 3.j 1. wide. Georgia. 



Body oblong-oval, flat, black, glossy : head black, with the elypeus and an 

 obsolete spot on the vertex, rufo-testaceous: palpi and antennae, similarly co- 

 lored: thorax, lateral margins, rufo-testaceous; anterior margin faintly dusky 

 reddish-brown : elytra irrovated with testaceous towards the lateral margins, 

 which are testaceous-yellow, and with a similarly colored fascia near the base, 

 curving a little at the suture and attaining the lateral margin ; three series of 

 remote impressed punctures, placed on narrow, somewhat faintly defined, ru- 

 fous lines : beneath black : posterior feet obscure reddish-brown ; intermediate 

 and anterior feet, rufo-testaceous: pleura; and epipleurx testaceous. 



Agabus, Leach. 



1. A. terminalis. Black, opake, densely and very finely striate; labrum, palpi 

 and antennas testaceous. — Nearly 5 1. long, 2^ 1. wide, Inhabits Pennsylvania. 



Colymbetes picipes, Kirby in Richards' Faun. Bor. Amer. IV. 71. 6 ] 

 Body convex, deep black, opake, densely and very finely striate : head with 

 two faint rufous spots on the vertex : antenna?, labrum and palpi testaceous or 

 rufo-testaceous: thorax with the basal impressed line distinct in the entire 

 width; apical impressed line finely punctured ; dorsal line indistinct: elytra 

 with three series of small, remote, impressed punctures, subsutural series most 

 distinct; tip acutely rounded: beneath and posterior feet black; anterior feet 

 reddish-brown, with the tibi and tarsi lighter. 



2. A. arctus. Black, glossy ; labrum, palpi, antennae and feet, pitchy-rufous. — 

 4} 1. long, 2j 1. wide. Pennsylvania. 



Body oblong-oval, convex, with the sides subparallel ; deep black, tinged 

 with bluish, shining ; head each side, between and near the eyes, with three 

 small indentations; epicranial spots obscure: antennae, labrum and palpi 

 pitchy-rufous: thorax, sides subrectilinear ; posterior edge obsoletely piceous : 

 elytra with the sides almost parallel to near the apex, which is acutely rounded ; 

 three series of faintly impressed punctures : slightly brassy : venter with the 

 lateral margins piceous : feet dusky rufous. 



3. A. punctatus. Dull testaceous, glossy; elytra with three double irregu- 

 lar series of punctures; pectus black. — 4 1. long, 2 1. wide. Virginia. 



Body oblong-oval, convex, dusky rufous, or dull testaceous, glossy: head 

 antenna; and palpi, rufous: eyes glaucous, with a black central dot: thorax 

 dusky on the middle; the ordinary series of punctures on the anterior and pos- 

 terior margins distinct ; arese of the posterior angles, and posterior moiety of 

 the lateral margins, with scattered punctures: elytra dusky on the disk ; very 



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