Crystal Cyst Formation in Parenchymatous Tissue. 177 
cates the direction of the plasma pressure and the direction of concentration 
of the calciuni oxalate. 
A fact which serves as a logical argument is the striking peculiarity 
that, while the extreme outside parenchyma cell rows contain less water and 
consequently show mostly polyhedric crystals, the inside cell tissues contain 
more water, and therefore show monoclinic crystals. 
There are formed, therefore, two rings which resemble those of Liese- 
gang ( 29 - 31 ). This striking relation between these different crystal regions 
and the colloid theory of Liesegang can be observed in other cases, i. e. in 
two neighbouring cells with calcium oxalate crystals of different forms. 
This phenomenon is very common in nearly any plant tissue. Although an 
indirect application of the theory of Liesegang is possible in these cases of 
different crystal formations in the parenchymatous tissue, there is not yet 
sufficient material at hand to make a suggestion for a direct relationship 
between the colloidal theory and the cell fusion before the crystal 
formation. 
The formation of calcium oxalate crystal cysts, whereby large cell 
complexes of the parenchymatous tissue are destroyed, must eventually have 
an effect on the physical appearance of the plant. Although such has not 
yet been observed, it is certain that the plant will show some effect as soon 
as the normal function of the vesicular elements are disturbed by the 
increase in the formation of the cysts. 
Summary. 
After having studied the crystal cysts of the genus Anthurium , the 
following final statements can be made : 
1. Two different crystal regions separated from each other exist in the 
parenchymatous tissue of the perianth leaves of AntJmrium scandens and 
A. Scherzerianum , of which the outside region consists of polyhedric 
crystals, while the inside is characterized by monoclinic raphid crystals with 
more water than the former. 
2. The region of the monoclinic crystals is further distinguished from 
the other where polyhedric crystals occur, in that in the former fusion 
of cells and their nuclei occurs and precedes the crystal formation, while in 
the latter no fusion takes place. 
3. Symplasts are formed as a result of cell and nuclear fusion, whereby 
often the whole parenchymatous tissue of the organ is dissolved. 
4. The formation of the symplasts consists mainly in the gradual 
increase in the density of the protoplasm of two neighbouring cells and 
the subsequent hypertrophy of their nuclei. The latter assume positions on 
opposite sides of a common cell wall. After this cell wall has been broken 
N 2 
