of Buprestidze and Elateridee. 211 
Thomson has shown with much ability the details of this point 
of structure in Elateride. 
Throughout the whole series up to Campylus the ventral sur- 
face of the abdomen retains the same peculiarities, being horny, 
hard, arched, with sharp edges, and so composed that only the 
last segment is moveable—a circumstance which, even in dried 
specimens, is distinguishable by the fact that the membrane 
between the last two segments is bare. In Campylus, however, 
the ventral surface is flatter and softer, particularly along the 
side edges, where it is almost quite soft, and all the segments 
are moveable. This is in itself an indication of the power of 
clicking h€ving in Campylus become a subordinate point, as in 
Melasini and Eucnemidini, though there it is due to a develop- 
ment of the type in an entirely opposite direction ; for whilst in 
Campylus the faculty of springing yields the first place to the 
development of the legs, it is in the two groups just mentioned 
the power of flight which is increased at the cost of the “ click- 
ing.” But in Campylus we meet also with another important 
circumstance—namely, that the elytra do not, as in other genera 
of this family, fit into a groove on the pronotum, but protrude 
freely above its posterior edge. Amongst the digging Elateridz 
or Cebrionini this arrangement is only met with in Cebrio. 
The preponderance which, in conformity with this, is accorded 
to the legs, shows itself in several peculiarities—for instance, in 
this, that the fore legs cannot, as in other Elateridze, be accom- 
modated inside the hind corners of the pronotum, which there- 
fore are continued backwards in the form of a spout. These 
remarkable and important peculiarities in the structure of Cam- 
pylus have hitherto been overlooked; and thus it has not only 
been classed together with such genera as Hemiops and Plectro- 
sternus, with which it has in reality nothing to do, but authors 
have even placed in the genus Campylus itself such species as 
E. homalismus, lig., and others, which do not resemble C. line- 
aris or C. denticollis in anything except in general outline and 
habitus, but entirely differ from them in the structure of the 
sternum, limbs, and abdomen, and therefore must find their 
proper places in other genera of Elateride. 
Be8ides Campylus there ig one other Danish genus of this 
family in which the pronotum is not arranged for receiving the 
base of the elytra in its hind margin, and in which, therefore, in 
like manner the springing-joint is without the essential support 
afforded by this articulation. Campylus shows by its whole 
structure that this want is connected with a reduction of the 
springing-faculty in all points, and an increased development 
of the limbs. We might therefore at first sight be surprised to 
find the same want of support in the articulation in a genus 
15* 
