1833.] PHOSPHORESCENCE OF THE SEA. 163 
As we proceed further southward the sea is seldom phospho- 
rescent ; and off Cape Horn I do not recollect more than once 
having seen it so, and then it was far from being brilliant. This 
circumstance probably has a close connexion with the scarcity of 
organic beings in that part of the ocean. After the elaborate 
paper * by Ehrenberg, on the phosphorescence of the sea, it is 
almost superfluous on my part to make any observations on the 
subject. I may however add, that the same torn and irregular 
particles of gelatinous matter, described by Ehrenberg, seem in 
the southern as well as in the northern hemisphere, to be the 
common cause of this phenomenon. The particles were so 
minute as easily to pass through fine gauze; yet many were dis- 
tinetly visible by the naked eye. The water when placed ina 
tumbler and agitated, gave out sparks, but a small portion in a 
watch -glass scarcely ever was luminous. Khrenberg states that 
these particles all retain a certain degree of irritability. My 
observations, some of which were made directly after taking up 
the water, gave a different result. I may also mention, that 
having used the net during one night, I allowed it to become 
partially dry, and having occasion twelve hours afterwards to 
employ it again, I found the whole surface sparkled as brightly 
as when first taken out of the water. It does not appear pro- 
bable in this case, that the particles could have remained so long 
alive. On one occasion having kept a jelly-fish of the genus 
Dianeea till it was dead, the water in which it was placed became 
luminous. When the waves scintillate with bright green sparks, 
I believe it is generally owing to minute crustacea. But there 
ean be no doubt that very many other pelagic animals, when 
alive, are phosphorescent. 
On two occasions I have observed the sea luminous at con- 
siderable depths beneath the surface. Near the mouth of the 
Plata some circular and oval patches, from two to four. yards in 
diameter, and with defined outlines, shone with a steady but pale 
light ; while the surrounding water only gave out a few sparks, 
The appearance resembled the reflection of the moon, or some 
luminous body ; for the edges were sinuous from the undulations 
of the surface. The ship, which drew thirteen feet water, passed 
* An abstract is given in No IV. of the Magazine of Zoology and 
Botany. 
