T1IE “SKIPJACKS” AND THEIK ALLIES. 169 
depressing the head and thorax, and elevating the 
middle, so as both to free the dagger-like projection 
of the prothorax from tho sternal groove, and obtain 
a purchase for its rapid re-insertion, which is ac- 
companied by a sharp clicking sound : tho effect of 
this is to make tho end of the abdomen and elytra act 
as a lever, whereby the insect is elevated to a con- 
siderable distance in the air, nearly always coming on 
its logs, which aro too short, and too closely articulated 
to tho body, to enable it to reach the ground in any 
othor way. If unsuccessful in its first endeavour, it 
persists in skipping until it lands itself right side up. 
Tho wings in this family are ample, and the flight 
strong ; many of its members flying in tho hot sun- 
shine, and basking in warm places ; though others are 
nocturnal, or at least crepuscular, in their habits. 
Tho British spocios may bo divided directly into 
seventeen genera, or into threo tribes, tho Agrypnina, 
Elaterina, and Campylina ; of which the first is dis- 
tinguished by its antennal being receivod into tho 
furrows of the prostornum in repose. Our sole un- 
doubted species, Lacon murinus, a broad, somewhat 
convex, and mottled-grey insect, is found in garden 
heaps and grassy places. The prostornal furrows aro 
not open behind, and there aro no lamellae to its tarsi 
beneath. 
The Elaterina present no decided character beyond 
having tho antenna) froo in repose : they comprise a 
groat number both of genera and species, all possessing 
a certain family likeness, but whoso divisions are 
comparatively artificial. The typical genus Elater 
comprises somo flattish shining-black insects with 
blood-red elytra, and one species, E. sanguinolentus 
