$4 Observations upon Luminous Animals. 
other. Some navigators have actually described this species 
of medusa, without being aware of its nature. Mr. Bajon, 
during his voyage from France to Cayenne, collected many 
luminous points in the sea, which, he says, when examined 
by a lens, were found to be mmute spheres. They disap- 
peared in the air. Doctor Le Roy, in sailing from Naples 
to France, observed the sparkling appearance of the sea, 
which is usually produced by ‘the medusa scintillans. By 
filtering the water, he separated Juminous. particles from 
it, which he preserved in spirits of wine: They. were, he 
says, like the head of a pin, and did not at all resemble 
the nereis noctiluca, described by Vianelli; their colour 
approached a yellow brown, and their substance was ex- 
tremely tender, and fragile. Notwithstanding this. stri- 
king resemblance to the medusa scintillans, Le Roy, in con- 
sequence of a preconceived theory, did not suppose what 
he saw were animals, but particles of an oily or bituminous 
nature *, 
The minute globules seen by Mr. Langstaff in the Indian 
ocean, were, T think, in all probability, the scintillating 
species of medusa; and on my showing him some of these 
animals I have preserved in spirits, he entertained the same 
opinion. 
Professor Mitchell, of New York, found the luminous 
appearance on the coast of America to be occasioned by 
‘minute animals, that from his description plainly belonged 
to this species of medusa, notwithstanding which, he sup- 
posed them to be a number of the nereis uoctiluca * 
The luminous animalcule discovered by Forster off the 
Cape of Good Hope, in his voyage round the world, bears 
so strong a resemblance to the medusa scintillans), that T 
am much disposed to believe them the same. He describes 
his animalcule as being a little gelatinous globule, less than 
the head of a pin; transparent, but a littie brownish in its 
colour; and of so soft a texture that it was destroyed by 
the slightest touch. On being highly magnified, he per- 
ceived on one side a depression, i in which there was a tube 
that passed into the body, and communicated with four or 
five intestinal sacs. The pencil drawings he made on the 
spot are in the possesston of Sir Joseph “Banks, by whose 
permission engravings from them are subjoined to this pa- 
per. By comparing these with the representations of the 
‘medusa scinvilins, and some of this species rendered visi- 
* Olserv. sur un Lumiere produite par & Eau de la Mer. Mem. Elrang. des Sc. 
Phil, Mag. vol. x. p. 20, 
ble, 
