Page:Natural History, Mollusca.djvu/337

Rh 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 luminosity 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 the temperature of the atmosphere on deck was 52°, and that of the water 51½°. The luminosity of the water gradually decreased during the night, and towards morning was no longer seen, nor on any subsequent night."