392 INSECTA. 



Elmis, Lat. — Limnius, lUig- 



They A'e found in water, under stones, or on the leaves of the 

 Nymph3ea(l). 



3. Those in which the always very short antennse consist of 'but 

 six or nine joints, and terminate in an almost solid, oval, or nearly 

 globular club. 



MACuoNYcnus, Mull. Germ. 



These Insects have five distinct joints in the tarsi, an oblong body, 

 and antennse of six segments, the last of which — perhaps composed 

 of three — forms an oval clubj they can be folded under the eyes(2). 



Georissus, Lat. Gyll. — Pimelia, Fab. 



Here the tarsi consist of but four joints; the body is short, tur- 

 gid and almost globular, and the abdomen embraced by the ely- 

 tra; the antennae are composed of nine joints and terminate in a 

 round club formed by the ihreo last(3). 



FAMILY V. 



PALPICORNES. 



In our fifth family of pentamerous Coleoptera, as in the 

 fourth, we observe antennsB terminating in a club, usually 

 perfoliaceous, but consisting of nine points at most in all, and 

 inserted under the lateral and projecting edges of the head; 

 they are never much longer than the latter and the maxillary 

 palpi, and frequently even shorter than the last mentioned 

 organs. The mentum is large and scutiform. 



The body is usually ovoid or hemispherical, convex or 

 arched. The legs in several are adapted for natation, and 

 then consist of but four very distinct joints, or of five, the first 



(1) Latr., lb., II, p. 49; Schoenh., lb. I, ii, p. 117; Gyllenh., Insect. Suec. I, 

 p. 551. 



(2) Macronychus quadntuhercidatus, Miill.; lllig'., Mag., V; Lat., Gener. Crust, 

 et Insect., II, p. 58; Parnus obscurus. Fab. ; Germ., Insect. Spec. Nov., I, p. 89. 



(3) Pimelia pygmsea. Fab., Georissus pygmxus, Gyll., Insect. Suec, I, iii, p. 675; 

 Trox dubius, Panz., Faun. Insect. Germ. LXII, 5. 



