134 
LA.NTHORN-FLIES. 
[Nature and Art, October 1, 186fi. 
tion of the non-appearance of luminosity in Fulgora 
might be given. Those who have studied the 
economy of the glow-worm and other well-known 
luminous insects, will agree with us, that the 
brilliant light which the creature emits is the lamp 
of love, and burns only at that season in which — 
“ So like a bride, scented and bright, 
She comes out, when tho sun’s away.” 
We well remember taking home a glow-worm, 
just such a one as many of our young readers 
may have seen in that interesting little book, 
entitled “ The Butterflies’ Ball and Grasshoppers’ 
Feast;” and placing it in our London garden, we 
many a night had the pleasure of watching its soft 
green lustre ; but one night, alas ! it had vanished. 
Before going to bed, however, we threw up the 
window and, gazing downwards, perceived, as we 
thought, two glow-worms glistening below us ; 
suddenly they vanished, and now again we saw 
them moving rapidly above our garden wall — they 
were only the eyes of a cat ! The true glow-worm 
had ceased to shine, for its luminous season had 
passed. 
If, then, these insects have their seasons of bright- 
ness, why should not the lantliorn-fly also have 
a set time in which to light its lamp 1 
Dr. Hagen certainly appears to take this view : 
he says, “ May it not possibly be the case that 
Fulgora is only luminous at certain seasons 1 ” He 
also proposes another explanation of the mystery, 
namely, that the luminosity may be confined to 
one sex, this being, according to all analogy, ex- 
tremely likely. 
As to the reality of the luminosity of this insect 
at times, the following facts seem to our mind 
conclusive : — 
As far back as 1685, Nehemiah Grew, M.D., 
notices the fact ; lie, however, states that the 
Indians fasten two or three to a stick, and thus 
obtain sufficient light to work, or to travel by. 
Now, although Mr. Grew gives a figure of the 
Fulgora, it is possible that lie may in this matter 
have been misinformed, as the very thing is known 
to be done with the Elater noctilucus, or fire-fly. 
Madame Merian, in her work upon the insects 
of Surinam, not only asserts her belief in it, but 
informs us that the first discovery which she made 
of this property caused her no small alarm. The 
Indians had brought her several of these insects, 
which, by day-liglit, exhibited no extraordinary 
appearance ; and she enclosed them in a box until 
she should have an opportunity of figuring them, 
placing it upon a table in her lodging-room. In 
the middle of the night, the confined insect made 
such a noise as to awaken her, and she opened the 
box, the inside of which, to her great astonishment, 
appeared all in a blaze ; and in her fright letting it 
fall, she was surprised to see each of these insects 
apparently on fire. She soon, however, divined 
the cause of this unexpected phenomenon, and 
reinclosed her brilliant guests in their place of con- 
finement. She adds, that the light of one of these 
flies is sufficiently bright to read a newspaper by. 
In opposition to this, it has been urged that 
Madame Merian was sometimes incorrect in her 
statements, in support of which it is said, that she 
asserts the fact of the large American spider, 
Mygale avicularia, feeding upon small birds ; yet 
this is not so supremely ridiculous an idea as might 
be supposed, for in Mr. Bate’s Naturalist on the 
Amazons, we find the same truth recorded. 
In 1837, Mr. R. M. Martin fully corroborates 
the truth of the luminosity of the lantliorn-fly in 
the “History of the West Indies,” vol. ii., page 
184 (vol. v. of the British Chemical Library). 
We need not, however, go so far back for informa- 
tion on this head ; in 1858, Dr. J. A. Smith ex- 
hibited a specimen of the Fulgora laternaria aj; a 
meeting of the Royal Physical Society of Edin- 
burgh, and he observed that it was still an 
undecided question amongst naturalists whether 
these flies were really luminous at any time ; it was 
therefore of importance that the undoubted evidence 
of eye-witnesses should be produced. Mr. Banks, 
of Prestonpans, who had forwarded the specimen 
exhibited, was therefore at once requested to 
obtain further information from his correspondent 
on that particular point. 
On the 27tli of April, 1859, at a subsequent 
meeting of the same society, Mr. James Banks 
communicated through Dr. Smith, the reply of his 
correspondent at Honduras to the question raised 
at the society, Mr. Banks had received several 
letters upon the subject of the luminosity of 
Fulgora, and they all bore testimony to the truth 
of the statement, that this fly emits light. A letter 
from Mr. Alexander Henderson, of Belize, furnished 
the following details 
“ In answer to the question, 1 Is it really luminous ? ’ 
certainly the fly possesses light, and therefore emits it. 
The light is evidently under control, for it increases and 
diminishes at pleasure. When the wings are closed there 
are three luminous spots on each side of the head-piece on 
the upper part (like a cat’s staring' eyes) of a beautiful 
sulphur-coloured light, in rays that spread over the room. 
The third luminous spot is seen when the fly is on its back, 
half-way down the abdominal part of the insect. When 
quiescent the lumination is least ; in daylight the upper 
spots are nearly white, emitting no light whatever (its 
lively time is at twilight). Immediately on being agitated, 
or moving about, the spots become sulphur colour and 
radiate forth streams of light, clearly seen, although the 
sun be shining into the room, as it now does at the moment 
I write, with the creature in the glass tumbler before me. 
We shut out the light, and to test the power of the fly I 
took up a book and read two verses of the 109th Psalm. 
Mr. Robert Gregg also took up a book and read by its 
light. I hope this will satisfy all, that the lanthorn-fiy 
is luminous.” 
Notwithstanding all this, we see in the Zoologist for 
1863, that Mr. Robert John Jeffry, of New Grenada, 
cannot tell why it is called the “ lanthorn-fly,” for 
it gives no light ; he imagines that the use of the 
subdiaphanous projection is to preventthepoorstupid 
insect from injuring itself by knocking against hard 
substances during flight, the head at such times 
acting as a sort of buffer. Mr. Kirby, however, who 
believed in the luminous properties of the insect, 
imagined that the lanthorn which must necessarily 
precede the insect when on the wing, might act the 
