320 Luminousness of the Sea. 
white; found in the Straits of Malacca. The other (jg. 83. 7) 
belongs to a genus unknown to me. It is exceedingly nimble 
in its ‘motions : ; the head, which is rather large and unshapely, 
was enveloped in a membranous bag, which seemed also 
extended over the whole body. It was quite transparent, the 
body spotted with bars of a dark colour. Found in the South 
Atlantic Ocean. 
In drawing up this paper for the Society, I have not gone 
to any length to endeavour to prove that the luminousness of 
the sea is caused solely by the presence of animalcules, and this, 
for the following reason, viz., that there scarcely now exists 
a doubt upon the subject. Any arguments which I could have 
produced may be found much better expressed and more 
forcibly illustrated by referring to Dr. Macculloch and Mr. 
Macartney. I should like, however: to make two remarks 
before I close this, I am afraid, uninteresting paper. 
In the first place, then, I should like to correct an error into 
which, I conceive, Dr. Macculloch has fallen, an error pro- 
duced by his wandering a little into theory, and neglecting facts 
and experience. He has stated that in general, when the sea is 
luminous, we will find the colour of the water to be greenish ; 
and, on the other hand, that we will never see the blue water of 
the ocean possessed of a luminous appearance; “ for,” says he, 
“the phenomenon is never seen except when animalcules are 
present in the water, and the blue colour of the ocean depends 
upon the circumstance that there are no animalcules to be 
found in it, therefore we will never find this water to be 
luminous.” I perfectly agree with him as to the cause of the 
light given out by the sea; ‘but, I humbly conceive; with regard 
his other statement, ian is decidedly incorrect. Not only 
does the luminousness of the sea occur in blue water, but I 
have myself caught numerous animalcules in it, which evi- 
dently produced that luthinous appearance ; and this fact will 
be found, instead of invalidating his former opinion, to 
str engthen it the more, as it shows clearly that in all parts of 
the sea, when the water is possessed of a luminous quality, 
there animalcules are to be found. 
2dly, It is an opinion held by sailors, and which is to be 
found as having prevailed amongst that class of people from 
the earliest times, that the luminousness of the sea is a fore- 
runner of stormy weather; and this opinion has even been 
taken up and defended by several authors, who have written 
upon this subject. Having long been aware of this fact, it 
amused me not a little to observe a work published about two 
years ago, in which the author very modestly assumes to him- 
o 
self the merit of the discovery, that this appearance in the sea 
