of Buprestidee and Elateride. 179 
series of forms as those of Cerambycide, but in a less degree. In 
these latter the collar of the prothorax varies not a little in ex- 
tent according to groups and genera, the head being in some cases 
deeply inserted into the prothorax, in others tolerably free ; but, 
in all of them, so much at least of the principal portion of the pro- 
thorax remains that, at any rate on the underside, it appears as a 
transverse fold which carries the short legs when such are found. 
To the larvee of Lami correspond those of Buprestide, to that of 
Trachys the larvee of Lepturini, in which the head is sometimes 
so little inserted that it seems to betray a relationship to those 
larvee of Curculiones which burrow in timber. When the head 
occupies such a position as in the larve of Buprestidae, being 
inserted in the prothorax, the skin of the neck must necessarily 
be very full, in order to afford the necessary play for the pro- 
trusion and retraction of the head ; and in proportion as the in- 
sertion of the head is deeper, the skin of the neck is fuller and 
more protruding. 
It will now appear that although none of the theories above 
mentioned have hit upon the facts, they all contain in some way 
an element of truth. Loéw’s view is purely anatomical, and 
although wrong in a morphological sense (because the mandibu- 
lar muscles cannot well be situated in the prothorax of any insect 
with articulating mandibles), yet it is so far true that the head 
which contains them is itself imbedded in the prothorax ; what 
Low has overlooked is the walls of the head. Goureau’s view 
is, so to say, that of common sense unshackled by anatomical 
or morphological scruples; and from such a point of view the 
prothorax might be called the head with perfect justice. Erich- 
son’s view is learned and critical, with a theoretical element 
inviting attention, but is neither probable in a physiological 
point of view nor true in point of anatomy ; it has therefore less 
of body or soul than either of those it attempts to reconcile. 
What he considers the hind part of the head is merely the dis- 
tended skin of the neck. 
III. 
The striking external similarity between the larvee of Melasis 
and those of the Buprestidze has not only served as a principal 
argument for looking upon Melasis as a connecting lmk between 
Elateridz and Buprestide, and thus exercised a decisive influence 
on all the more recent attempts at a new classification of the 
Sternoxi, but it has at the same time weighed heavily against 
the probability of finding in the study of the larve a sure guide 
to the true classification of insects—a circumstance which Ericn- 
son has not omitted to mention in the introduction to his in- 
structive treatise on the larvee of Coleoptera (in Archiv f. Natur- 
13* 
