458 \V. DE MOEGAN AND THE LATE G. HAROLD DREW. 



follows that a certain amount of active metabolism is going on within the 

 mass, and from the disappearance of the cell debris, nematocysts, ova, 

 etc., which are included in the restitution masses when first formed, it 

 would seem at least possible that these may be absorbed and used up in 

 the metabolic processes of the living cells. Similarly the living cells may 

 feed on those which degenerate. 



SYNOPSIS OF EXPERIMENTS. 



Numbers omitted belong to experiments not dealt with in this paper. 



Experiment 1. — A colony of Antennularia antennina dredged on 

 5th December, 1911, was allowed to stand through the night in " out- 

 side " water, and at 10 a.m. on 6th was squeezed into watch-glasses con- 

 taining a little Berkefeld water, through 50 mesh bolting silk. 



Aggregation commenced about 12 noon, and the watch-glasses were 

 then placed in finger-bowls of Berkefeld water. Under the microscope 

 no direct motion of the cells towards one another was noticeable. The 

 cells gravitated downwards and adhered together to form small spherical 

 nodules. These were shaken towards the centre of the watch-glass and 

 left for the night. 



On the morning of the 7th nearly all the stuff had united to form 

 irregularly shaped plates from 1 to 2 mm. in length connected by narrow 

 strands. In various spots there were club-headed vertical upgrowths 

 from the plates. The whole aggregate, which was greenish yellow in 

 colour, was surrounded with a tough perisarc, no space appearing between 

 it and the contents. 



By the 8th considerable contraction of the interior mass was noticed. 

 There was a clear space between the perisarc and the contained matter, 

 and clear spots were seen here and there in the plates. The contents of 

 the club-headed upgrowths also contracted. 



On the 9th these cultures were found swarming with Infusoria and 

 Flagellates, and they were fixed in Corr. Sub. It was thought then that 

 Protozoa would injure the culture ; experience proved that they are not 

 harmful. 



Experiment 3. — Colonies of Antennularia antennina collected on 

 12th December, 1911, and kept 24 hours in Berkefeld water. Squeezed 

 through 180 mesh bolting silk, 11 a.m., December. 13th. By 3 p.m. 

 small spherical masses had formed. On the 14th no change had occurred, 

 the small spheres forming a film over the bottom of the watch-glass. 

 Microscopical examination showed cells with a broken outline ; and small 



