188 REVISION OF THE BUPRESTIDM® OF THE UNITED STATES. 
have observed in every great group, some exceptions to the form presented by the ma- 
jority of the species of the same group: this appears to me an objection to combining the 
eroups, perfectly natural in themselves, into larger series which are defined by the posi- 
tion of these antennal pores; and this is the only point in which I have diverged from 
the arrangement of Lacordaire. 
The characters of the family have been already exposed by me in my revision of the 
Elaterids of the United States, but may be briefly recapitulated as follows: 
Cox antice parvee, globose, non contiguee, in acetabulis e prosterno et mesosterno 
compositis receptee: prosternum pone coxas productum in mesosterno vel etiam in metas- 
terno receptum; abdomen sutura ventrali anteriore plus minus obliterata, segmentis 1 et 
2 connatis: tarsi 5 articulati, articulis 1-4 vel 8-4 subtus lobis membraneis instructis: 
antennee serratee, articulis externis preecipue poriferis: ocull integri, elliptici. 
The character deduced from the consolidation of the two anterior segments of the ab- 
domen has been called in question by Kiesenwetter, Ins. Deutschl. iii. 6, and 50, (but his 
observations seem to be defective, (vide infra Ancylochira;) and although the suture be- 
tween these two segments is frequently visible, it never permits of any movement like the 
other ventral sutures. 
In some genera the species approximate so clearly as to present the phenomena of races: 
instances will be seen in Clirysobothris, Agrilus, and perhaps in Dicerca and Chalcophora. 
The groups of genera, as defined in the following paper may be thus tabulated: 
* Front not contracted by the insertion of the antenna. 
A. Prosternum obtusely or scarcely angulated on the sides, tip obtuse, (except in Cinyra,) mesosternum divided. 
I. Mesosternum closely anchylosed with metasternum; antennal pores lateral. Gyascutus, Chalcophora, Psi- 
loptera. 
II. Mesosternal suture distinct; antennal pores marginal. Dicerea, Poecilonota, Ancylochira, Cinyra. 
IIL. B. Prosternum acutely angulated on the sides, acute at tip; mesosternum divided. Melanophila, Anthaxia. 
IV. C. Prosternum short, broad, obtuse, not angulated on the sides; mesosternum rarely divided. Thrincopyge, 
Chrysophana, Polycesta, Ptosima, Acmzeodera. 
* * Front contracted at the insertion of the antenne. 
V. Prosternum acutely angulated at the sides, acute at apex; mesosternum narrowly divided; mentum corncous 
at base, membranous at tip. Chrysobothris, Actenodes. 
VI. Prosternum cuneate, not angulated on the sides; mentum large corncous, front perpendicular, mouth in- 
ferior, applied to the prosternum.- Coraebus, Agrilus. 
VII. Prosternum not angulated at the sides, apex cuneate, fissured, or truncate: mesosternum very widely di- 
vided; front inflexed, mouth inferior, applied to prosternum; mentum large corneous; legs contractile, tarsi very 
short. Brachys. 
VIL. Prosternum broad, truncate, front perpendicular, mouth inferior free, mentum large corncous; legs not con- 
tractile. Taplostethus. 
