60 INSECTA. 
Cnopaton, Lat. 
Where, from the fifth joint, the antenne are strongly compressed 
and serrated, and where the head is much narrower than the thorax*. 
CampsiA, Lepel. and Serv.—Camaria, Id. 
Where the antennz, from the sixth joint, are slightly serrated, 
and the head is as wide as the posterior margin of the thorax. The 
body is proportionally longer and less convex, and the thorax wider 
posteriorly f. 
In all the other Helopii, the mesosternum presents no remarkable 
emargination, and the posterior extremity of the praesternum is not 
extended into a point. 
Here the body is sometimes ovoid or oval, and at others more 
oblong but narrowed at both ends; it is never cylindrical or linear, 
nor much flattened. Certain subgenera have been formed with He- 
lopii, which approach the first in their strongly inflated body, which 
is gibbous posteriorly. 
Those, in which the body is almost ovoid or short, and the thorax 
transversal, plane or simply curved, compcese the following sub- 
genera, 
SpueEniscus, A irby. 
Easily mistaken at the first glance for Erotylus, and in which, as 
in the preceding subgenera, the inner side of the last joints of the 
antennee are dilated like the teeth of a saw, and the thorax is plane f. 
Acantuorpus, Meg. De). 
Shorter and rounder than the Insects of the preceding subgenus, 
with simple antennz terminated by a larger and ovoid joint; the 
anterior thighs inflated and dentated, at least in one of the sexes, and 
the tibize almost linear with very short spurs, or almost none ; ante- 
rior tibize arcuated §. 
Amaryemus, Dalm.—Cnopaton, Hetops, Curysomea, Fab. 
Allied to Acanthopus, with simple but filiform antennze, and the 
anterior thighs neither inflated nor dentated. All the tibiz are 
straight and terminated by very apparent spurs |]. 
* Lat., Gener. Crust. et Insect., II, p. 182, and I, x, 7. 
+ Encyc. Méthod., article Sphenisque. Messrs. Lepeletier and Serville give but 
ten joints to the antenne of the Camaria, a character which would distinguish them 
from the other Helopii: but we have distinctly seen eleven in various Helopii from 
Brazil, which appear to us closely allied to the C. nitida, quoted by them. Until we 
can verify this anomaly in the individuals examined by those gentlemen, we think it 
best to unite the two subgenera. LBesides the Cnodalon irroratum of Germar, 
quoted in this article, refer the Toxicum geniculatum and nigripes, ejusd., to the same 
subgenus. 
t Spheniscus erytoloides, Kirb. Lin. Trans., XII, xxii, 4; Encyc. Méthod., article 
Sphenisque. The Helopii suturalis and geniculatus of Germar form the passage from 
this subgenus to Helops proper. 
§ Helops dentipes, Panz., Ross. ;— Helops dentipes, Fab., another species, but 
from the East Indies. 
|| Dalm., Anal. Entom., p. 60. The Helops ater, Fab., should also be referred 
to this subgenus, 
