876 DR R. KIDSTON AND PROF. W. H. LANG ON OLD RED SANDSTONE PLANTS 
Occurs in a cavity of a decayed stem of Rhynia Gwynne-Vaughani in the lowest 
bed (A'T) of the deposit. 
Locality. — Muir of Rhynie, Aberdeenshire. 
Horizon. — Old Red Sandstone. (Not younger than the Middle Division of the 
Old Red Sandstone of Scotland.) 
The filamentous organism described as Schizophyta No. 2 above, may provisionally 
be placed under the same generic name as Archasothrix contexta. 
ALGITBS, Seward. 
1894. Algites, Seward, Catal. Mesoz. Plants in British Museum, pt. i, p. 2. 
3.- Algites (Palaionitella) Cranii, n.sp. (PI. IX, figs. 98-104.) 
We give this name to some fragmentary remains of a plant that was clearly an 
Alga. While, in the absence of distinctive reproductive organs, it is impossible to 
determine its systematic position, certain characters of the vegetative organs will 
be seen to present resemblances to those found in existing Characese. 
The name is applied in the first instance and the species is founded on specimens 
of septate filaments, occasionally with evidence of the existence of nodal discs of 
small cells, which have been met with in a few blocks of the chert. These remains 
are of the type represented in figs. 98-104 and text-figs. 6-11. 
We associate with these remains some remarkable specimens of more uncertain 
nature found in a loose block of the chert by the Rev. Mr Cran of Skene in prepara- 
tions he had made while studying the animal remains in the chert. Mr Cran 
generously handed his preparations and drawings to us for description, and we have 
great pleasure in naming after him the undoubted algal remains mentioned in the 
preceding paragraph. The actual specimens he discovered (figs. 91-97 and text-figs. 
1-5) are not treated as the type but, for the present at least, are regarded as to 
some extent incertae sedis ; they are, however, with some confidence associated with 
Algites Cranii. 
In the same way we provisionally place in association with this species some 
peculiar globular or oval vesicles and filaments accompanying these (figs. 105-108). 
These are of interest and require to be recorded, but their nature is still uncertain. 
They were obtained from blocks removed from the bed in situ. 
The type specimens will first be described, and then these specimens of more or 
less uncertain affinity, but of morphological interest, will be dealt with. 
The general appearance of a portion of a section showing a characteristic group 
of the remains of Algites Cranii in the peaty matrix is represented in fig. 98. The 
prominent structures are stout septate filaments with dark contracted remains of the 
protoplasmic contents of the cells. Some of the filaments are more highly magnified 
in fig. 99. The tip of a filament is sometimes seen as at a in fig. 98 ; it ends in a 
