DIURNAL PERLODICILY OF PLLOSPLLORESCENCE, 23 
Drary or HXprERIMEN'S 
Monday, September 21st, 1908 (8-30 p.m.)—Calm night, and sea very 
phosphorescent. Collected plant (Polysephonia nigrescens) from the rope 
of an old mooring buoy. ‘he plant is covered over with phosphorescent 
organisms which flash most brilliantly. The specimen is preserved in 
sea-water and examined ashore. It shows most brilliant phosphorescence 
when rubbed. When a piece is put in fresh tap water in the dark it 
lights up most brilliantly all over for about three minutes, then gradually 
the light fades out, and cannot now be evoked by any process of shaking or 
rubbing. 
Tuesday, September 22nd.—The plant was taken into the dark room 
at 11 a.m. and examined; no phosphorescence could now be evoked by any 
process, either shaking in air, stirring up in the sea-water, rubbing, 
applying fresh water. 
A tow-netting had just been taken in the Bay (12 noon). This was 
taken into the dark room at once, but no trace of phosphorescence could 
or 
be obtained from it, even with most vigorous stirring. 
In the evening, from 9 to 9-30 p.m., a tow-netting was taken in the 
Bay, the sea being very phosphorescent wherever touched by the oars. The 
haul, when taken into the boat, scintillated most brilliantly while being 
washed into sea-water in a jar. The contents of the jar, taken into the 
dark room at the Station, are showing spontaneous phosphorescence, and 
give a vivid show when stirred. Left in the dark room over-night. 
Wednesday, September 23rd—Kxamined the previous night’s tow- 
netting at 11 a.m.; there is not a trace of phosphorescence to be elicited, 
even on stirring briskly. Examined at intervals all day in the dark 
room. ‘There is not a trace of phosphorescence seen till about 6-30 p.m., 
when sparking first starts on stirring, just as it is growing dusk outside, 
and at 7 p.m. there is spontaneous phosphorescence. 
Took also during the day three tow-nettings from a row-boat, each of 
15 minutes’ duration, at 12-45 to 1 p.m., 3-45 to 4 p.m., and 5-15 to 
0-30 p.m. As each tow-netting was finished, it was taken to the Station, 
at once emptied into a flat pie-dish, and taken to the dark room to be 
