324 TUNICATA.—SALPADA. 
light around to a far stronger degree, illuminating 
the ship. On taking in the towing-net, it was 
found half filled with Pyrosoma (Atlanticum?), 
which shone with a beautiful pale-greenish light ; 
and there were also a few shell-fish in the net at 
the same time. After the mass had been passed 
through, the light was still seen astern, until it 
became invisible in the distance; and the whole of 
the ocean then became hidden in darkness as be- 
fore this took place. The scene was as novel as 
beautiful and interesting ; more so from my having 
ascertained, by capturing luminous animals, the 
cause of the phenomenon. 
‘The second occasion of my meeting these crea- 
tures was not exactly similar to the preceding; 
but though also limited, was curious, as occurring 
in a high latitude, during the winter season. It 
was on the 19th of August, the weather dark and 
gloomy, with light breezes from north-north-east, 
in latitude 40° 30° south, and longitude 138° 3’ 
east, being then distant about 868 miles from 
King’s Island (at the western entrance of Bass’s 
Straits). It was about eight o'clock p.M. when the 
ship’s wake was perceived to be luminous; and 
scintillations of the same light were also abundant 
around. As this was unusual, and had not been 
seen before, and it occasionally, also, appeared in 
larger and smaller detached masses, giving out a 
high degree of brilliancy,—to ascertain the cause, 
so unusual in high latitudes during the winter 
season, I threw the towing-net overboard, and in 
twenty minutes succeeded in capturing several 
Pyrosomata, giving out their usual pale-green 
light ; and it was, no doubt, detached groups of 
these animals that were the occasion of the light 
