206 : MISS A. L. SMITH ON THE DEVELOPMENT 
These so-called “cilia” appear at first as slightly thickened 
irregular outgrowths towards the growing points of the thallus. 
They become larger, and consequently more crowded, as the fruits 
ripen. 
A section through a mature cystocarp presents the appearance 
shown in Pl. XXXV. fig. 5. There is a broad pericarp enclosing 
a central mass of spores; the outer layers of the pericarp are 
of small, closely adhering cortical cells, the inner layers are of 
larger cells. Immediately surrounding the spores, we often find 
seemingly elongated much-erusbed cells very full of contents. 
The spores themselves are arranged in larger or smaller groups, 
each occupying its own compartment, and mostly separated from 
the other groups by a broader or narrower wall of thallus-cells 
elongated and compressed like those that surround the whole 
mass. 
The spores are irregularly round or oval; they vary in size 
and shape. They lie in loose groups, or sometimes in regular 
rows and chains of connected spores. Occasionally we find a 
little packet still surrounded by an outer cell-wall, showing that 
division is not yet quite completed. 
The main axis of the thallus is a solid mass of apparently 
parenchymatous tissue. The medullary part consists of very 
large cells interwoven with smaller cells which have more abun- 
dant contents. The cortex is of radiating filaments of still 
smaller cells, more regular in size and closely packed together. 
In the outgrowths destined to hold the eystocarps, we find the 
large medullary cells are smaller and richer in contents than the 
cells of the vegetative thallus; the interstitial cells seem to be 
more numerous; the cortex is thicker, forming a strong compact 
envelope for the future fruit. This thickened cortex is already 
present to some extent when the procarps first appear. 
At a very early stage, various cells of the outer medullary 
tissue and inner cortex are differentiated from the rest, and 
become densely filled with protoplasm. Some of these cells, 
auxiliary cells we may call them, are large and irregularly shaped 
(Pl. XXXV. figs. 1 & 2). They continue to grow apparently 
at the expense of the surrounding tissue. Along with these are 
smaller eells exactly similar in contents. 
These differentiated cells go to form the procarp, but I have 
failed to trace their relation to each other, whether they all 
