GEODEPHAGA. 
73 
The JDromii, small, elongate, flattened beetles, often 
ornamented with four whitish spots, are found mostly 
under — or in the chinks of — bark, where they subsist 
upon other subcortical insects. 
Odacantlia melanura, a narrow, cylindrical species, 
with head and thorax bluish-green, and reddish elytra 
and legs (the apex of the former, and joints and feet 
of the latter, being blue-black), is found in the stems 
of reeds in the Cambridgeshire fens and elsewhere ; 
Drypta dentata, occasionally taken in some numbers 
out of clay-banks at Alverstoke, Hants, is conspicuous 
for its lovely, silky, azure clothing, and the very long 
basal joint of its antennae; and Lionychus quadrillum, 
an obscure little bronze-black insect, with two dull 
lighter-coloured spots on each wing-case, is noteworthy 
from its haunting wet shingle and stones on the coast, 
in Devonshire and at Southend. 
The species most likely to have been seen by casual 
observers is the tiny Bleclirus maurus, which may be 
noticed darting rapidly over sun-dried pathways, 
reminding one of an animated grain of gunpowder ; 
and the one which has made most noise in the world 
is the ‘ Bombardier,’ Brachinus crepitans, a mode- 
rately small rusty-red fellow, with dull blue-black 
wing-cases, and a narrow head and thorax (Plate I., 
Pig. 3). It is abundant on the south coast, especially 
under chalk, on the banks of the Thames below 
Gravesend ; where, in the month of August, a dozen 
may be found under one stone, the explosion of whose 
’ stern-chase ’ guns sounds like a Lilliputian battery. 
The noise is caused by a peculiar fluid secreted by the 
insect, which, being emitted from its lower extremity, 
