__ 380" 
The disporangia have the same position as the tetrasporangia, but in the spe- 
cimen in question, two or even three lateral organs were often borne on the same 
joint. As a rule one of the lateral organs was a sterile 
branch, the other a sporangium, but two sporangia 
might also occur on the same joint, the youngest 
under the eldest. A sporangium may be placed under 
the branch, but more frequently beside it (fig. 279 B). 
The disporangia which are usually sessile, but some- 
times borne on a one-celled stalk are 56—70 w long, 
35—40 w broad. They have always a double outer 
wall, just like the tetrasporangia. 
The tufts of paraspores are, as well known, ter- 
minal on the long shoots, and I usually found them 
so, but lateral tufts, sessile or borne on a unicellular 
or bicellular stalk are sometimes met with on the 
upper branches, thus with a similar position to that 
ofthe sporangia. The usual terminal tufts of paraspores 
are sharply delimited 
downwards, all the 
cells of the axis above 
a certain level and its 
branches being trans- 
formed into paraspo- 
res, their form beco- 
ming rounded, their 
contents much con- 
densed and the wall & 
thicker. The branches 
Fig. 279. of the tufts are crow- 
Seirospora GrifRihsiana. Disporangia: ded, and frequently 
A, two very young sporangia on the 
same joint. B, sporangia besides or two branches are bor- 
under a ire = at 1. C 200 :1. ne on the same joint. 
The outer wall of the 
cells in the tufts is thick and at first homogeneous, 
but later on it is often composed of two or three 
layers each of which has a firmer outer mem- 
brane. In the middle of the dense dark-red contents 
Fig. 280. 
a Sr = 7 re Seirospora Griffithsiana. Typical tuft of 
a large nucleus is visible after staining. A transiti- paraspores. 215 : 1. 
onal stage between the terminal and the lateral para- 
spore-tufts is shown in fig. 281, the lowermost one or two cells in the upper branch- 
es being sterile. In other cases similar lateral tufts of paraspores are found at a 
greater distance from the apex, borne on a two-celled or one-celled stalk or even 
