96 Observations upon Luminous Animals. 
nearly at the posterior angles of the corcelet, and are more 
loose in their texture than the oval masses of the noctilucus, 
resembling rather in composition the interstitial substance 
which surrounds these masses in. that species. The shell 
of the corcelet is somewhat thinner, and more transparent 
along both sides of the margin, than at other places ; but it 
is not, as in. the palaces elevated, and peculiarly 
clear and thin immediately over the seat ‘of the luminous 
organ: consequently, the light emitted by the elater ignitus 
cannot be very brilliant, 
I have not been able to procure any specimen of the elater 
phosphorea, but from the accounts of naturalists it appears 
to resemble in every respect the elater noctilucus; indeed 
: have great doubts of the phosphorea being a ‘distinct 
ecies. 
I have had an opportunity of examining, preserved in a 
Moist wav, two species of fulgora, the candelaria and Janter- 
naria. , The light in this genus has been observed to  issne 
from the remarkable proboscis on the fore part of the head. 
This part has always been described by authors as hollow 
or empty, which I have found te be perfectly correct; and 
what is more extraordinary, that the cavity communicates 
freely with the external air, by means of a chink or narfow 
aperture, placed on each side of the root of the proboscis. This 
projection is covered internally by a membrane, between 
which and the horny part or shell there appears to be in- 
terposed a pale reddish coloured soft substance, that is ar- 
ranged in the candelaria in broad lines or stripes ; but it is 
so thin, that 1 could rot distinctly examine its structure, 
or absolutely determine, whether it should be considered as 
a substance intended to farnish the light of these inseets, or 
the pigment upon which the colour of the proboscis de- 
pends. 
The globes of the antennz constitute the organs of light: 
in the pausus spherocerus, Dr. Atzelius, who. discovered 
the luminous property in this species, compares them to 
lanterns spreading a dim phosphoric light *. ‘The rarity of 
the insect put it out of my power to examine its structure ; 
but from the form and situation of its organs of heht, it is 
most probable they are constructed like those of the ful- 
gore. 
It has been conjectured by Carradori and others, that the 
lampyrides were enabled to moderate or extinguish their 
light, by retracting the luminous substance under a mem - 
* Linn. Trans, vol. iy. 
brane ; 
