175 
the Prothalhis of Equisetum debile , Roxb . 
separated from each other by at least two layers of cells, one layer forming 
the lateral wall of each. In the ripe state, however, the cells of these layers 
become compressed, and sometimes it is not possible to distinguish them. 
In the young state they may be separated by a single layer of cells 
(Fig. 33). 
The chromatin in the spermatogenous cells in the early stages of 
antheridial development is deeply stained with gentian violet in preference 
to safranin when treated with the triple stain, as is stated by Chamberlain. 
Later on the chromatin is stained more deeply with safranin. The blepharo- 
plast was seen in sections when the nucleus had assumed the parietal position 
and had begun to curve (Fig. 36). About this stage the spermatozoid 
mother-cells, which are already separate from each other, begin to develop 
a mucilaginous degeneration of their wall, and in sections or teased-out 
cells mucilage processes are seen spreading out in all directions from the 
wall, giving the cell a stellate appearance. 
Ihe mature spermatozoid (Fig. 37) is spirally coiled and flattened 
throughout the greater part of its body. The anterior end is rounded and 
bears numerous cilia. Quite a large part of the body is formed by 
chromatin and the blepharoplast. The length of the spermatozoid exclusive 
of cilia is about 20 //. It is practically the same as the length of a sperma- 
tozoid of E. arvense , as given by Sharp, i. e. 19*7 /x. 
