PHOSPHORESCENCE OF THE SEA. 209 



recollect more than once having seen it so, and 

 then it was far from being brilliant. This circum- 

 stance 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 6upei"fluous 

 on my part to make any observations on the sub- 

 ject. 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 heinisphere, to be the common cause of 

 this phenomenon. The particles were so minute as 

 easily to pass through fine gauze ; yet many were 

 distinctly visible by the naked eye. The water, 

 when placed in a tumbler and agitated, gave out 

 sparks, but a small portion in a watch-glass scarce- 

 ly ever was luminous. Ehrenberg 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 du- 

 ring one night, I allowed it to become partially dry, 

 and having occasion twelve hours aftenvards to 

 employ it again, I found the whole sui-face spark- 

 led as brightly as when first taken out of the water. 

 It does not appear probable, in this case, that the 

 paiticles could have remained so long alive. On 

 one occasion, having kept a jelly-fish of the genus 

 Dianaea till it was dead, the water in which it was 

 placed became luminous. When the waves scin- 

 tillate with bright green sparks, I believe it is gen- 

 erally owing to minute Crustacea. But there can 

 be no doubt that very many other pelagic animals, 

 when alive, are phosphorescent. 



On two occasions I have observed the sea lumi- 



* An abstract is given in No. IV. of the Magazine of Zoology 

 and Botany. 



Vol. I—n S 2 



