of Buprestide and Elateride. 189 
although a slight indication of it may be found in some cases, 
where the posterior part of the epimeron is somewhat bent out- 
wards. It is even very rare to find the pronotum and epimera pro- 
thoracica separated by a real suture (as in Carabide) ; nay, it often 
occurs that the suturesbetween the pronotum, prosternum, and the 
epimera become to such a degree effaced that the entire prothorax 
seems to consist of only one piece (as in most Curculionidee). In 
Buprestidee and Klateridze all these parts are immoveably united, 
but the seams between the prosternum and epimera are always 
to be recognized, and the junction of the epimera and pronotum 
is marked by the more or less sharply raised lateral edges of the 
latter. It follows that the Buprestidie possess no episterna on 
the prothorax, any more than any other insect, unless that ap- 
pellation is to be given to the large lateral shields themselves 
which are commonly called epimera. Von Kiesenwetter regards 
the true epimera as laterally inflected parts of the pronotum, 
and gives the name of episterna to the prolongations of the 
prosternum (which other authors equally erroneously call tro- 
chantins), and thus he comes to the result that the prothorax in 
Buprestidee consists of pronotum, episterna, and prosternum, 
but in Elateridze of pronotum and prosternum alone (Nat. Ins. 
Deutl. iv. p. 217), whereas the prothorax in both families con- 
sists of the same pieces as in other insects, viz. pronotum, pro- 
sternum, and epimera prothoracica, as shown before. 
Vi. 
Anybody who has watched nature a little in field and forest 
knows full well that faculty in the H/ateres which has procured 
them the popular name of spring-beetles. It would therefore 
be natural to expect that the peculiar contrivance by means of 
which these beetles are enabled, when placed on their back, to 
toss themselves up in the air and fall down on their legs, had 
long ago been so thoroughly investigated and understood by 
scientific entomologists that it could always with certainty be 
decided whether any given species is endowed with this faculty 
or not. But this is very far from being the case; it is still a 
moot point with regard to many animals of the Elater-type 
whether they can spring or not, so that, generally speaking, one 
is not satisfied till one has seen the thing done before one’s own 
eyes ; and with regard to this mechanism there is but little agree- 
ment amongst entomologists, except concerning the cases where 
the articulation of the prothorax and mesothorax is sufficiently 
loose to allow us to inspect easily the whole structure and pro- 
ceeding. This latter has been familiar for a very long time; and 
short and correct accounts of it are given in old manuals, as 
by Latreille in Cuvier’s ‘Régne Animal.’ It is true that some 
