198 Barker . — The Morphology and Development of 
previous writers. It has also been stated that the subsequent 
stages, visible in the living condition, consist of an apparent 
conspicuous vacuolization of the protoplasm of the central cell, 
and eventually the formation of spores within it. We have 
seen that the apparent vacuolization is due to the formation 
of much entwined hyphae, produced and practically surrounded 
by the much enlarged and curiously-shaped central cell ; and 
that the spores are formed in small spherical asci arising from 
these internal hyphae. It has also been shown that these 
structures can only be seen at all clearly when the material 
has been suitably fixed and stained at all the different periods 
in the development of the perithecia. 
It would not be surprising, therefore, if the earlier observers 
had overlooked these facts. From what has been brought 
forward it seems probable that they did overlook them, and 
this is rendered fairly certain from their papers and figures. 
Considering Went’s paper first, it has already been noted 
that, when the investing hyphae had formed a more or less 
complete covering to the central cell or ‘ sporangium,’ the 
behaviour of the latter was obscured. In a few cases it was 
possible to observe changes in the protoplasmic contents of 
the ‘ sporangium,’ which first presented the appearance of 
containing large vacuoles, this stage being followed by a 
somewhat similar phase in which the vacuoles were smaller 
and the structure more foam-like, these features in the end 
becoming so pronounced as to render the internal structure 
indistinguishable, which continued until spores appeared. 
Although the author searched carefully he was not able to 
discover the exact period or method of spore-formation. His 
figures, which accompany the paper, include examples of all 
these stages. Bearing in mind the fact that he was dealing 
with living material, we notice that the apparent structures 
of the ‘ sporangium,’ which he has described, are in essentials 
identical with the stages observed above under similar con- 
ditions. But we have seen that the apparent vacuolization is 
really due to the formation of hyphal branches from the 
‘ sporangium, ’ which organ has more or less surrounded them 
