Crystal Cyst Formation in Parenchymatous Tissue. 161 
The difficulty of observing bacteria in cells filled with a dense mass of 
protoplasm is well known to histologists. Since the investigations on this 
subject are not )^et concluded, at present no final judgement may be given. 
In the further development of the cysts the nuclei of the two cells 
assume positions on opposite sides of the common cell wall. Later the 
wall is ruptured and a fusion or mingling of the cell contents and the nuclei 
occurs. PI. II, Fig. i, shows the large cell which probably arose by the fusion 
of two other ceils and which lies in the centre of the parenchymatous tissue. 
The hypertrophied cell thus produced is about twice as large as the 
neighbouring cells. The protoplasm containing numerous small and large 
vacuoles is strikingly dense and displays an embryonic character. The 
nucleus gives the impression of having recently arisen by the fusion of two 
other nuclei. 
The nuclei of the neighbouring parenchymatous cells generally are not 
far distant from the hypertrophied nucleus. PI. II, Fig. i, shows the nucleus 
of the cyst lying in one corner of the enlarged cell, while the nuclei of the 
neighbouring cells lie near the cell walls in the immediate vicinity of the 
large nucleus. The fusion nucleus may or may not retain its normal 
spherical form. In some cases a further fusion of cells with the cyst takes 
place and their nuclei fuse with that of the cyst. In other cases the 
nucleus of the cyst becomes deformed and may assume a spiral shape. 
This phenomenon usually occurs in old organs. In immature organs 
a further fusion of the cyst with the surrounding cells takes place. PI. II, 
Figs. 2 , 5 , ii, and Text-figs, i, 3 , 4 , and 5 , show fusions or pairing of nuclei. 
In PI. II, Figs. 3 and 4 , both nuclei lie within the plasma ring that was formed 
by the union of the two cells. 
Further enlargement of the cyst at the expense of the neighbouring 
cells causes a breaking down of the common cell wall and the dissolving of 
the remnants. This process results in the formation of a large symplast. 
PI. II, Figs. 8 , 11 , and Text-figs. 1 and 3 , show clearly how the walls are 
pierced and the cell nuclei are enabled to fuse with the principal nucleus. 
Fragments of cell walls undergoing solution are plainly visible. 
It happens very often that two young neighbouring symplasts fuse 
together. Text-fig. I demonstrates such a case which was observed in the 
third cell row from the epidermis in the perianth of Anthurium Sellerze- 
rianum . In one part of this fused cyst we find some nuclei in the act of 
fusing, while the nucleus of the other part has more or less an elongated 
form, without, however, any crystal formation in that particular part. The 
nuclei of the surrounding parenchyma cells maintain their round form. 
Within the cell, during the process of cell fusion, the protoplasm layer of 
the cyst is increased in thickness and an extensive crystallization of calcium 
oxalate takes place. 
The first colony of raphids is formed in the immediate vicinity of the 
M 2 
