214 
BRITISH BEETLES. 
and very convex, is exclusively devoted to Mercunalis 
perennis, the leaves of which are riddled by it to a 
large extent : Orepidodera, distinguished by the abrupt 
depression in the middle of the base of the thorax, 
comprises several insects of bright and metallic colours, 
C. helxines, am- at a, and clitoris being especially bright ; 
of these the first is the largest and broadest, found on 
poplars, with entirely yellow antennae and legs (except 
the hind femora), uniformly coppery, green, or blue, 
and with the thorax not so roughly or closely punctured 
as the second, which is smaller, occurs on willows 
abundantly, has its antennm, and sometimes its legs, 
more or less suffused with dark, and its thorax often 
of a different colour to its elytra. C. clitoris, found on 
poplars, is narrower than aurata, always unicolorous, 
and with four joints at the base of its antennal yellow, 
the remainder being abruptly black. 
The species of Mantura are remarkable for their 
cylindrical shape, — affording a gTeat contrast to the 
larger and pallid Spliscrodcrmx, which resemble 
nothing so much in structure as half a microscopic 
orange, with the flat side down. 
Aphthona contains some inconspicuous forms, some- 
what resembling certain of the genus Thyamis, from 
which they may bo distinguished by the basal joint of 
their hinder tarsi being much shorter. 
The species of Phyllotreta are especially addicted to 
the destruction of cruciferous plants ; certain of them 
being known as the “ Turnip-flea ” or “ -fly,” on 
account of their ravages upon that vegetable, the 
leaves of which are both mined by their small elongate 
dotted larvae, and devoured by the perfect insect. 
They are mostly black ; often having on the elytra 
