SWIMMING ASCIDIANS. 325 
in question. The beautiful light given out by 
these molluscous animals soon ceased to be seen 
emitted from every part of their bodies; but by 
moving them about, it could be reproduced for 
some length of time after. As long as the lumi- 
nosity of the ocean was visible (which continued 
most part of the night), a number of Pyrosoma 
Atlanticum, two species of Phyllosoma, an animal 
apparently allied to Leptocephalus, as well as 
several crustaceous animals (all of which I had 
before considered as intertropical species), were 
caught and preserved. At half-past ten p.m. the 
temperature of the atmosphere on deck was 52°, 
and that of the water 514°. The luminosity of 
the water gradually decreased during the night, 
and towards morning was no longer seen, nor on 
any subsequent night.” * 
* Wanderings, vol. i. 
