126 THE HAUNTS OF LIFE 
just the reflection of scant gleams of light and 
is never seen in total darkness—when animal 
light is best seen—there is something quite 
useful in the comparison, for the luminous or- 
gans have often reflectors not very different 
from the reflector in the back of the cat’s eye. 
In any case, “animal light” is common in 
the deep sea, both in fixed and wandering 
creatures. The light-giving stuff or secretion, 
which remains luminescent after the animal is 
dead, often oozes out on the general surface, 
as in sea-pens, and may trail into the water. 
In its finer forms, in fishes and crustaceans, 
it shines out from complicated lanterns, the 
special luminous organs. 
The Marquis de Folin, who was with one 
of the great French expeditions, describes the 
surprise and delight of the naturalists on 
board the exploring vessel when they first saw 
a deep-sea dredge brought up in darkness. 
The dredge contained many coral animals, 
shrub-like in form, which threw off “flashes 
of light, beside which the twenty torches used 
for working by were pale.” Some of the corals 
were carried into the laboratory, where the 
lights were put out. “There was a moment 
of magic, the most marvellous spectacle that 
