A STUDY OF RESTITUTION MASSES. 461 



1st February. Still healthy in appearance. The contents have 

 further contracted away from the perisarc. Fixed for examin- 

 ation. 



Experiment 17. — 31st January, 1912, noon. Squeezed colonies of 

 Antennularia ramosa through 50 mesh, and placed in finger-bowls of 

 Berkefeld water, 4 p.m. The temperature of the Laboratory is so high that 

 these bowls were placed in a trough of running water. 



1st February. Lobate masses, 1 to 2 mm. in length, surrounded by 

 perisarc have formed. 



2nd. The lobes have further contracted, and most of the masses are 

 attached to the glass. 



2nd to 11th. Very little change observable except slight contraction 

 by which a space was left between the contents and the perisarc. Clearer 

 spaces appeared also in the body of the mass. 



20th. One mass now 20 days old and thoroughly healthy in appear- 

 ance fixed. 



21st. Several small masses still alive. In the largest of them con- 

 traction of the contents at various points has resulted in a markedly 

 spongy appearance, as shown in the figure. This is observable in a less 

 degree in other smaller masses. 



9th March. All remained alive up to this date, and without any 

 apparent change. From this date onward the contents appear to be 

 gradually degenerating — in one or two of the masses the enclosing perisarc 

 is almost empty. 



21st. The spongy appearance of the large mass is gradually changing, 

 and the contents appear to be concentrating in the centre. This culture is 

 now 51 days old, and has still a healthy yellow colour. Similar concen- 

 tration has taken place in one or two of the smaller masses which were 

 fixed for examination. 



Exferiment 23. — 1st March, 1912, 11 a.m. Squeezed fine colonies of 

 Antennularia ramosa through 50 mesh. Aggregation of cells commenced 

 almost immediately. 



3rd. Of the three cultures made on the 1st, two are not healthy. 

 Spherical masses have formed, but they look soft and fiocculent, and the 

 perisarc is not clear and smooth. 



The third culture, however, has resulted in a healthy lobed mass, not 

 attached to the glass — deep yellow in colour and with a smooth perisarc. 

 The edges of this mass are folded over into knobbed ridges, round a 

 thinner central plate. There is a nearly vertical cylindrical mass at 

 one end. 



