s6‘4, Mr. Macartney’s Observations 
led me to the coast, I have had many opportunities of making 
observations upon the animals which illuminate our own seas. 
Of these I have discovered three species : one of which is a 
beroe not hitherto described by authors ; another agrees so 
nearly with the medusa hemispherica, that I conceive it to be 
the same, or at least a variety of that species ; the third is a 
minute species of medusa, which I believe to be the luminous 
animal, so frequently seen by navigators, although it has 
never been distinctly examined or described. 
I first met with these animals in the month of October 1804, 
at Herne Bay, a small watering place upon the northern coast 
of Kent. Having observed the sea to be extremely luminous 
for several nights, I had a considerable quantity of the water 
taken up. When perfectly at rest, no light was emitted, but 
on the slightest agitation of the vessel in which the water was 
contained, a brilliant scintillation was perceived, particularly 
towards the surface; and when the vessel was suddenly struck, 
a flash of light issued from the top of the water, in consequence 
of so many points shining at the same moment. When any 
of these sparkling points were removed from the water, they 
no longer yielded any light. They were so transparent, that 
in the air they appeared like globules of water. They were 
more minute than the head of the smallest pin. Upon the 
slightest touch, they broke and vanished from the sight. 
Having strained a quantity of the luminous water, a great 
number of these transparent corpuscles were obtained upon 
the cloth, and the water which had been strained, did not 
afterwards exhibit the least light. I then put some sea water 
that had been rendered particularly clear, by repeated Ultra- 
tions, into a large glass, and having floated in it a fine cloth* 
