HEMIPTERA. 33 
very distinct joints, the last with two’ terminal hooks. ‘The an- 
tennz appear to consist of but three joints, the last of which is 
the largest and ovoid(1). 
The antefnz of the following genera are quadriarticulated, and 
the anterior tarsi terminate simply in a point or hook. 
Navcoris, Geoff. Fab. 
The labrum in Naucoris is not emarginated, as is the case in the 
following genus, but is exposed, large, triangular, and covers the 
base of the rostrum. The body is almost’ ovoid and depressed, and 
the head rounded; the eyes are very flat. The antenne are simple 
and without any projection in the form of a tooth. ‘There is no sa-. 
lient appendage at the posterior extremity of the abdomen. The 
four last legs are ciliated, and their tarsi consist of two joints, with 
two hooks at the end of the last. 
NV. cimicoides; Nepa cimicoides, L.; Roes., Insect., III, Cim. 
Aquat., xxxviil. Five or six lines long, and of a greenish brown, 
lighter on the head and thorax; margin of the abdomen serrated 
and projecting beyond the elytra(2). 
In the three following subgenera, the labrum is sheathed, and the 
extremity of the abdomen presents two filaments. 
Betostoma, Lat. 
Where all the tarsi are biarticulated, and the antennz are semi- 
pectinated(3). 
. 
‘Nepa, Lat. 
Or Nepa proper, where the anterior tarsi have but one joint, and 
the four posterior ones two, and where the antennz appear forked. 
The rostrum is curved beneath; the coxz of the two anterior legs 
are short, and their thighs much wider than their other parts. 
Their body is narrower and more elongated than in the preceding 
subgenera, and almost elliptical. Their abdomen is terminated by 
two setz which enable them to respire in the oozy and aquatic 
localities at the bottom of which they live. Their eggs resemble 
the seed of a plant of an oval figure, crowned with a tuft of hairs. 
(1) Lat. [b., ILL, p. 144; Nauwcoris oculata, Fab. 
(2) Fab., Syst. Ryng.; Lat., Gener. Crust. et Insect, II, p. 146. 
(3) Lat., Ib., p. 144; the Nepa grandis, annulata, rustica, Fab. 
Vou. IV.—E 
