330 
Fault . — The Cytology of 
covered by a filmy colourless ‘ chitinous ’ envelope (PI. XXXVII, Fig. 2). It 
is noteworthy, too, that the protoplasm and nuclei of all the cells of the 
appendages, even in older plants, are apparently well nourished, and that 
they never show indications of decay. This is in contrast with the larger 
cells of the receptacle. The protoplasm in the latter often becomes very 
scanty and loosely reticulate, and the nuclei frequently have every appear- 
ance of being in a state of decadence, as is manifested by the fact that they 
sooner or later lose their sharp outlines, their contents show little or no 
structure, and sometimes an irregular, densely staining nucleolus accompanied 
by a greater or smaller mass of equally densely staining debris is all that 
remains of them. This disorganization is rarely, if at all, seen in the 
appendages. 
The septa in the receptacle are resolvable into several layers, of which 
the middle lamella stains purplish and the others yellowish. The former 
is continuous with the darkly stainable layer in contact with the general 
envelope (Figs. 8 and 9). On it the others are superposed, the younger 
being less compact and more hyaline than the older. The septa separating 
daughters of the same mother-cell are single pitted (Fig. 7), so that there 
is a continuous protoplasmic tract from the base of the plant to the tips of 
the appendages. 
The septa of the appendages are constructed like those of the receptacle, 
but are rather thicker than might be expected after what has been said of 
their peripheral walls (Fig. 1). Their pits, too, are surprisingly large. In 
L. chaetophora and L. Gyrinidarum the septa are black as seen from the 
edge, but sections and face views show that the blackening is superficial 
and mainly restricted to the portion of the general envelope covering the 
rim of the septum. The septum stains reddish for a short distance out 
from the pit, then there is a wider yellowish peripheral portion, and then 
the black rim (Fig. 2, a). 
Protoplasmic Bridges. 
Possibly the most interesting features of the cell-walls are the pits and 
protoplasmic bridges. They are beautifully demonstrated and figured by 
Thaxter (’96) in Part I of his monograph, and it is strange that no reference is 
made to his descriptions by A. Meyer (’02), Kienitz-Gerloff (’02), Strasburger 
(’01), and other botanists who have examined various Fungi to discover 
whether or not they possessed these structures. 
De Bary (’84) appears to have been the first to note the existence of 
pits in the partition walls of the Fungi. He pointed out that they often 
possessed simple pits, and that those in Dactylium macrosporum were strik- 
ingly like those of the Florideae, such, for example, as in Callithamnion. 
The first work of any consequence on the subject of protoplasmic bridges in 
Fungi was done by Wahrlich (’92), who published an account of extensive 
