- INSECTA. 539 
Palps large, exsert. Elytra truncated. Tarsi short, with first joint 
minute. Body oblong, depressed. Abdomen broader than thorax. 
Small coleoptera, with almost the habit of Hispa or Alurnus, exotic, often 
met with, as it seems, in ants’ nests. Linn2xvs first founded the genus in 
A. Dauu Bigis Insectorum 1775, Amoenit. Academ. VIII. p. 307. Compare 
A¥zELIUS Transact. of the Linn. Soc. Vol. iv. p. 243, &c. and West- 
woop ibid. Vol. xvi. pp. 607—684, Pl. 33, and his Arcan. Entom. 1. 
pp. I—12, 37—40, 73—8o, 261—190. 
A. Head supplied posteriorly with a neck. 
Cerapterus Swep. Antenne with ten joints, club with nine 
joints. 
Compare N.S. SwEpERvS in Vetensk. Akad. nya Handb. 1788, p. 203. 
Pentaplatarthrus Westw. Antenne with seven or six joints, 
club elongate, broad, with five joints. 
Paussus L. Antennz with two or three joints, club broad, exar- 
ticulate. 
Sp. Paussus microcephalus L., Amoen. Acad. vit. Tab. vt. figs. 6—10; 
—Paussus thoracicus Donov., Pauss. trigonicornis Latr., Gen. crust. et 
Ins. 1. Tab. x1. fig. 8, &e. 
B. Head immersed in thorax. 
Hylotorus Daim. Antenne with two or three joints, club 
exarticulate, lanceolate, incurved, acuminate. Head furnished with 
two conical tubercles (ocelli ?). 
Sp. Hylotor. bucephalus GYLLENH. in ScHomnn. Syn. Ins. 1. 3, A pp. Tab. VI. 
hig, 2. 
Heterocerus Bosc. Antenne inserted under the lateral margin 
of frons, with eleven joints, first two large, broad, two following 
small, rest transverse, dilated, forming an elongated club. Head 
‘received within thorax almost to the eyes. Mandibles porrect, den- 
ticulate. Palps filiform. Body oblong, depressed, pubescent. 
Tibiz, especially anterior, spinose. Tarsi quadriarticulate. 
Sp. Heterocerus marginatus Fasr., DuméRit Cons. gén. s. 1. Ins. Pl. Thon. 
PanzER Deutschl. Ins. Heft 23, Tab. 12, &c. Small insects, the largest 
species of which is scarcely more than 2”” long, and which in all their states 
live in passages near the edge of the water. On the internal structure 
compare Léon Durour Ann. des Sc. natur. 2e Série 1. Zoolog. p. 60 and 
following, with figures. ‘ 
