On THE PITHOPHORACEA. 49 
l:st degree, solitary or opposite; spores inclosed (rarely terminal), single, 
eylindrical or subcylindrical, on an av. 106 w thick and 375 mw long. — 
Plate 1, figs. 1—38; pl. 4, fig. 1. 
[P. subvalida, filo principali partis thalli cauloidex speciminum fertilium circa 
127 w crasso, ramos unius solum ordinis, solitarios vel binos oppositos emittente; 
sporis inclusis (raro terminalibus), solitariis, cylindricis vel subcylindricis, c:a 106 u 
erassis et 375 w longis.] 
Locality. This species is found by Professor D:r E. v. MARTENS j:r in the 
moats outside the fortress at Palembang in Sumatra, the 29% of March 1862. — 
Epiphytically on the same grows a (sterile) Oedogonium which has been described, 
l. ec. pag. 20, by G. v. MARTENS s:r under the name of Conferva (Ocdogonium?) 
Cladophore. 
General Description. Fertile specimens. Cauloid part of the thallus. 
The rather few fertile specimens I have seen of this species have had branches 
only of the i:st degree. These have mostly occurred singly; but sometimes also 
two and two opposite to each other. The branches are always placed a little space 
below the top of the supporting cell. This space, however, is in general so short 
as to be smaller than the diameter of the branch. Neither accessorial branches nor 
helicoids have been observed. The spores are, as a rule, inclosed. Only one ter- 
minal spore I have observed, to wit, the sessile one represented in plate 1, fig. 1 st¢. 
The inclosed spores are found in the principal filament as well as in the branches. 
Their form is generally cylindric. Sometimes they are not at all swollen and then 
they are almost pertectly cylindric (pl 1, fig. 2); sometimes they are a little swollen 
and are then cylindrically cask-shaped (pl. 1, fig. 3). Twin spores I have not 
observed. 
Rhizoid-part of the thallus. I have seen only one specimen, the rhizoid 
part of which has not been broken off. This one quite accords as to the nature of 
the basal cell. with the specimen of P. @qualis nob: represented in pl. 1, fig. 6. 
Thus a rhizoid part had never been developed in this specimen. 
Sterile specimens resemble the fertile ones as to the ramification. In one 
of the examined specimens the basal part was preserved. This showed a rhizoid 
part consisting of one cell (pl. 4, fig. 1 rh), parted from the cauloid by an oblique 
cell-wall. 
Measurements. Fertile specimens. The vegetative cells of the principal 
filament are on an ay. 127 w thick; the smallest observed thickness is 105 yw and 
the greatest 150 uw. The vegetative cells of the branches are on an av. 92 w thick. 
They vary between 75 and 125 mw. The length of the cells is 5—25 times the 
thickness. Most frequently it is rather considerable, being 12—14 times the thick- 
ness. The inclosed spores are on an ay. 106 mw thick and 375 uw long. The limits 
of variation are indicated by {,/ 3) 333 w. The only terminal spore I have ob- 
served was 75 w thick and 555 w long. 
Sterile specimens. The thickness of the principal filament is on an av. 
137 mw; the smallest observed thickness is 115 w, and the greatest 180 w. The 
branches are on an ay. 95 mw thick; the smallest observed thickness is 75 and the 
greatest 110 uw. The length of the cells is about the same as in the fertile specimens. 
Nova Acta Reg. Soc. Sc. Ups. Ser. III. 7 
