336 On Aquatic Carnivorous Coleoptera or Dytiscide. 
I. 18.—Genus QUEDA. 
Coxal incision shorter in the longitudinal than in the transverse direction : only the 
fringes of the labrum visible; length 6 m.m. A single South American species. 
222. Queda compressa, n. sp.—Picea, nitida, convexa, lata, posterius angustata, 
et sat acuminata, elytrorum humeris rufis, antennis pedibusque rufo-testaceis ; dense 
sat fortiter punctata. Long. 54 m.m., lat. 3} m.m. 
Mas, antennis articulis 8-5, ceteris longioribus et latioribus. 
Fem., antennis articulis 3-5 ceteris longioribus haud latioribus. 
Of a compact and peculiar form, very broad in front and acuminate behind. 
Clypeus distinctly margined. Head finely and closely punctured. Thorax closely 
and rather finely punctured, the punctuation extending quite to the sides. Elytra 
closely, distinctly and evenly, but not coarsely punctured. Under surface distinctly 
punctured, the punctures on the hind coxz coarser than elsewhere, those on the 
ventral segments fine but numerous. A specimen in Bonvouloit’s collection, labelled 
“fulvipes Reiche Columbia,” is possibly a distinct species, being entirely black, and 
slightly longer. 
Brazil, (Sauta Rita, August and Sept. 1850, R. F. Sahlberg). 25. 
LI. 7.—Group Brpzsstnt. 
The posterior border of the hind coxz is completely soldered to the first ventral 
segment. ‘The hind coxal cavities are separated and not protected by the adpressed 
coxal processes. 
The soldering of the hind coxa to the ventral segment is peculiar to these 
insects, and occurs in no other Coleoptera. Except for this the other characters of 
the group are much the same as in the Hyphydrini. 
{ On the undersurface of head) HETERHYDRU, S, (vide p. 
Middle cox conspicu- the labrum is exserted. 337). 
ously separated, pro- 
sternal process broad { Only the anterior border ] 
and short with obtuse and fringes of labrum PACHY DRUS, (vide p. 338). 
hind margin. visibly exserted on under- 
side of the head. J 
Prosternal pro- | Middle coxe more ap- ) 
cess attaining 1 proximate, prosternal | 
the metaster- process rhomboidal, } = ROS OPACHRIA, (vide p. 
num. with acute termin- | 
ation. J 
sternal process. 
Prosternal processoblong. 4 
| Coxal lines shorter than the ) 1 a oO YDRUS, (vide p. 
| | prosternal process, 
Prosternal pro- } 
cess notreach- } 
ing to the me- | 
tasternum. | 
| 
| 
TYNDALLHYDRUS, (vide 
| : 
| | Coxal lines longer than pro- } BIDESSUS, (vide p. 344.) 
i p- 370.) 
