180 THE ENTOMOLOGIST’S WEEKLY INTELLIGENCER. 
Was Olivaceella only a form of transi- 
tion — doomed to become extinct ten 
years ago ? Much might no doubt have 
been made of this hypothesis, and pro- 
bably had the whole details been laid 
before Mr. Darwin, whilst his volume 
was in progress, we might have had 
another interesting chapter on the growth 
and modification of species. 
In May, 1859, we visited Brussels, 
and there obtained, from M. Fologue, a 
bred specimen of Olivaceella; it was 
bred from a case found on the stem of a 
tree; thus we did not learn the food- 
plant, but M. Fologne knew exactly 
where he had found it, and promised to 
look out for more. He kept his word; 
he bred several specimens last summer, 
and yesterday he sent us a box full of 
larvae. Larvm of an extinct species, or 
at any rate of a species that seemed to 
have become extinct ten years ago! 
This shows the necessity of caution, and 
of not jumping to conclusions. 
Some description of the case of the 
larva of Olivaceella may be interesting: 
it is cylindrical, ochreous-brown, with the 
mouth turned slightly downwards, and 
with a distinct ventral keel. The food- 
plant is Stellaria IJolostea ; in fact, 
Solitariella and Olivaceella feed lovingly 
on the same plant. 
If two closely allied species feed on 
the same plant mistakes are apt to occur. 
And the tissue of blunders respecting 
Olivaceella has been very extraordinary. 
For more than five years we have had 
in our cabinet two bred specimens of 
Olivaceella , but then we had placed them 
there as Solitariella. 
The history of these specimens de- 
serves a longer notice than we can 
give this week, but we shall recur to 
the subject on a future occasion; more- 
over, it has an important bearing ou 
the question of labelling insects and on 
journals generally. 
February 23, 1860. 
(To be continued.) 
LABELLING INSECTS. 
To the Editor of the ‘ Intelligencer.’ 
Sir, — I was much interested with 
Messrs. Wallace and Tyrer’s letters, 
which appeared in Nos. 173, 176 and 
177 of your valuable little paper; and, if 
you will allow me, I will say a few words 
on the subject. 
I think the numerals from 1 to 12 
preferable, as, according to Mr. Tyrer’s 
method, when the numbers reach up to 
a hundred or more, the pieces of paper 
would of course have to be much larger, 
and consequently would show, par- 
ticularly in the smaller species of Lepi- 
doptera. The first specimen in the 
Tineina would begin at once with some- 
thing like 1260, and these numbers, to 
read easily, without removing the insect, 
must be written on a moderately large 
piece of paper, so that the label would 
show on each side of the insect, and, as 
Mr. Wallace observes, would be offensive 
to the eye of a neat entomologist. 
For (Joleoptera I think the plan of 
numbering will prove invaluable; Cole- 
optera now-a-days being always carded, 
labels would not be required, as the 
numbers could easily be written on the 
under side of the card ; for instance, 
supposing my series consists of from four 
to six, according to the size or varieties 
of the insect, I would then number them 
from left to right, viz. 1, 2, 3, 4, 5, 6 ; 
besides they would also be numbered 
according to Mr. Waterhouse’s list; for 
example, I have a scries of Anchomenus 
