On THE PITHOPHORACE. 61 
or even four, if the wall marked cw’, and not that marked ww", was the one first 
formed in the germination. (Regarding this, see the paragraph on the germination). 
As to the specimens that are represented pl. 5, figs. 1 and 2, it is impossible to 
decide how much belongs to the rhizoid part, when it is not known with certainty 
which part of the specimens has belonged to the original, germinated spore. If 
the supposition were true, that the irregularly shaped organs marked sy are trans- 
formations of this spore, only the processes rh, pointing downwards, would belong 
to the rhizoid part. Sometimes no transversal wall is formed in the spore at the 
germination, and then the rhizoid either does not exist, or is only rudimentary. 
The former is the case if the germinating spore has not at all been elongated 
downwards (pl. 2, fig. 13 sgb; pl. 4, fig. 12 sgb; pl. 5, fig. 3 sy); the latter if it has 
been somewhat elongated, but without a parting wall between the cauloid and the 
rhizoid ‘having been formed (pl. 4, figs. 13 and 14 rh; pl. 5, fig. 6 rh). Pl. 4, fig. 
14 shows a case, when the forming of a parting wall was commenced, but without 
being completed. 
Sterile specimens differ from the fertile by stronger ramification — 
branches of the 2:d degree regularly existing — and by the branches being 
placed two and two opposite to each other as often as singly. j; 
Measurements. This species is the smallest one in the whole genus. Its ve- 
getative cells have, it is true, a greater diameter than those of P. kewensis nob., 
but the length of the individual cells as well as more especially of the whole plant 
is considerably less. The greatest specimens that I have seen have been only 25 
millimeter long, and specimens of a length of only 4-5 millimeter are not rare. 
Fertile specimens. Cauloid part of the thallus. The cells of the 
principal filament are on an average 70 w thick; the smallest observed thickness 
is 60 w and the greatest 90 uw. The cells in the branches of the I:st degree are 
on an ay. 55 w thick. The limits of variation are 50 w and 60 w. The branches 
of the 2:d and 3:rd degree are not much less thick than those of the I:st; the 
diameter of the cells is on an ay. 50 mw; the smallest diameter 45 w and the greatest 
55 w. The length of the vegetative cells is less in this species than in other 
species. Very short cells (1'/,-2 times as long as thick) eceur not seldom in the 
principal filament (pl. 4, fig. 13) as well as in the branches. Especially the cell 
just beneath a terminal spore has this form (pl. 5, fig. 4). Very long cells (such 
as in P. kewensis nob.) do not exist. Only very seldom the cells are 20 times, 
generally only 4—9 times as long as thick. The thickness of the terminal spores 
is on an ay. 93 w and their length, on an av. 232 w. The limits of variation are 
indicated by ‘74 ao, 20 L- The cask-shaped spores are on an av. 102 t thick, 
and 216 w long.. The limits of variation are indicated by {9 8) 120 1% uw. The 
cylindric spores are on an ay. 70 w thick and 164 u long. ‘Their limits of variation 
are ‘Tr 20, 220, 11, 210 M+ 
The cell of the rhizoid has a rather variable length. Most frequently it is 
very short, 1',,-4 times as long as thick (pl. 4, figs. 15 and 16), but sometimes it 
is more developed as to length, as much as 10 times as long as thick (pl. 4, 
fig. 17). 
