170 Rev. D. Landsborough on the 
with the Ser¢ularia upon it, receive a smart stroke with a 
stick in the dark, the whole. coralline is most beautifully illu- 
minated, every denticle seeming to be on fire.”?* I have lately 
discovered that it is not only prodaéle that many others ex- 
hibit the same phenomenon, but that it is absolutely certain 
that they do so. I had thought that in making the experi- 
ment it would be necessary to put the sea-weed to which the 
Sertularia was attached into a vessel of sea-water, but I find 
that it can be made with less trouble. 
About two months ago I brought from the shore in a pocket 
vasculum or tin-box, some zoophytes attached to sea-weeds, 
and laid the vasculum on the lobby table till I should have 
leisure to examine them. When night came I put my hand 
into the vasculum to remove some of the zoophytes for in- 
spection, and on moving them I found to my surprise and de- 
light that they began to sparkle. Remembering what I had 
read in the extract given above, as I took them up, I gave 
them a hearty shake, and they instantly became quite bril- 
liant, like handfuls of little stars or sparkling diamonds. To 
ascertain what were the zoophytes that emitted this phos- 
phorescent light, it was necessary to take them up singly by 
candle-light, and afterwards to make the experiment in the 
dark. The first I tried was Valckeria cuscuta, with which I 
was successful. From Sertularia polyzonias and Cellularia 
reptans little light arose ; Laomedea geniculata was very lumi- 
nous, every cell for a few moments becoming a star; and as 
each polype had a will of its own, they lighted and extin- 
guished their little lamps, not simultaneously, but with rapid 
irregularity, so that this running fire had a very lively appear- 
ance. Flustra membranacea also was very beautiful, though 
very different from the former ; for as the cells are so closely 
and regularly arranged, it exhibited, when shaken, a simul- 
taneous blaze, and became for a little like a sheet of fire. With 
Flustra pilosa I was very successful. That variety of it which 
is spread on a flat surface, and which, from the form that the 
polypidom assumes, is the Membranipora stellata of Thompson, 
on being bent or shaken, became doubly entitled to the name 
of stellated, for every polype in its cell lighted up a very bril- 
* Stewart’s Elements of Natural History, vol. ii. p. 425. 
