140 Buacksurn anp SHarp—On some New Species and Genera of Coleoptera. 
Group VII. 
B. obsoletus, Sh.; omalioides, Sh.; aper, Sh.; explanatus, Sh.; brevis, Sh.; 
spretus, Bl.; inaequalis, Sh.; striatus, Sh.; bicolor, Bl.; impressus, Sh. 
These insects are usually found in decaying vegetable matter, especially on 
the Freycinetia, where the decay of the basal parts of the leaves and of the fleshy 
interior of the flowers furnishes them with sustenance; they also occur in decaying 
fern stalks, and occasionally under bark. 
Hind body of male acuminate behind; supplementary segment generally well— 
sometimes very strongly—developed. Female usually coloured differently from 
the male. 
The tendency to paleness of colour in the female is a very singular character. 
It is not absolutely invariable; that is to say, the lightest coloured males and 
darkest females (in my series of the two or three species of which I possess a fairly 
long series) are not much unlike each other; but the great majority of females 
- are so much paler than the great majority of the males that at first sight one would 
take them to be different species. 
The following notes on the sexual characters of some of the species supply in- 
formation that the material in Dr. Sharp’s hands has not enabled him to furnish :— 
B. obsoletus. My material is insufficient for generalization regarding colour ; 
the one female I possess is paler than my one male, however. 
B. omalioides. Male almost always much clouded with fuscous, sometimes 
nearly black; its supplementary segment not large; female almost uniformly 
testaceous. 
B. aper. My material is insufficient for generalization regarding colour. 
B. explanatus. Female not known. 
B. brevis. The average colour of the female is very decidedly paler than that 
of the male. 
B. spretus. In my short series of this species two-thirds of the females are 
only a little paler that the lightest-coloured male, the remaining third are quite 
pale testaceous. 
B. ineequalis. I have examined only one male specimen; it has the supple- 
mentary segment less distinct than usual in this group. It is very much darker in 
colour than the female, which is evidently the sex described by Dr. Sharp. 
