of Buprestide and Elateride. 181 
ries, and beds for the pupa excavated in the solid timber? At 
first sight an attack seems hopeless on so strong a scientific 
fortress ; but a closer inspection will, I trust, discover more than 
one weak point. 
The structure of the larve of Buprestidee is easily understood, 
for in every point it exhibits with great consisteney the peculiar 
characteristics of an animal burrowing in wood. Such are the 
large head deeply seated in the prothorax, the short thick man- 
dibles formed like a hollow chisel, the large protruding labrum, 
the short, freely developed lower organs of the mouth, the 
powerful muscles of the neck, the broad prothorax beset with 
grains of chitine, the slender body adapted for creeping through 
galleries, the large anal segment, which is turned straight back- 
wards. If now the habits of the larva of Melasis are really the 
same as those of the larva of Buprestide, its structure must be 
identical with theirs at least in these principal points. But if 
the similarity only applies to the external structure, it is clearly 
insufficient, however striking, to prove a true affinity between 
these creatures, or even a similar way of feeding ; it merely justi- 
fies us in supposing that they live in similar localities and use a 
similar mode of locomotion. One would think that such a con- 
clusion, of which the truth is evident to common sense at every 
step in the study of living creatures, could not but be sufficiently 
appreciated and generally adopted. Nevertheless, as I have often 
urged on other occasions, no principle is oftener sinned against. 
No souree of errors in natural history flows more copiously than 
that which rises from the confusion of relationship with simi- 
larity, of affinity with analogy, of typical characteristics with 
biological modification ; so that it is but too clear that we have 
as yet advanced but very little towards the great aim of compre- 
hending the rational consistency of nature. It is this ancient, 
ever recurring mistake which also in this case has obscured the 
truth. 
For in spite of the positive and decisive appearance of the 
investigations just alluded to, they nevertheless embody a simple 
impossibility. Instead of a rasp-like chitinous armour on the 
prothorax, the larva of Melasis has merely a couple of narrow, 
partly transversely grooved bands of chitine, and its skin is 
generally thin and weak; the lower organs of the mouth are 
rudimentary, and coalesce into a small plate; the labrum is 
absent; the mandibles are pointed and bent outwards, they 
have a tooth on their back, and their inner margin presents 
merely a narrow unarmed edge; the head is free, rather soft, 
with only a few firmer bands of chitine forming a frame- 
work round the epistoma and hypostoma; the anal or tenth 
abdominal segment, which in the larva of Buprestide forms a 
direct continuation of the body, appears here merely as a small 
