» 
a 
110 Proceedings of the Royal Physical Society. 
Fig. 1a shows one of the leaves, which is very distinctly 
defined on the original; slightly enlarged. 
Fic. 2.—This is the other specimen which was figured 
by Messrs Jack and Etheridge, and is here given natural 
size. 
It shows a bifurcating branch. The specimen is a little 
indistinct at the base, and I am not sure that the lower part 
of the specimen is broken over—rather, I think, that it bends 
upwards again. At a a much smaller branch—perhaps a root 
—is given off. The leaves are not well shown, but the 
specimen is interesting as showing the bifurcation and the 
giving off of the small root-like branch a. 
Fic. 3, also natural size, shows portion of a stem denuded 
of its leaves, where the stigmaria-like appearance has been 
assumed. This specimen further illustrates the spiral 
arrangement of the leaves. ‘ 
Fic. 4 shows an enlarged leaf from another specimen. 
All these specimens were collected by Mr A. Macconochie, 
one of the staff of the Geological Survey of Scotland. 
Localities. —Fig. 1 (Reg. No. ™/488»), Fig.3 (Reg. No. “/492), 
and Fig. 4 (Reg. No. ™/484>) from quarry west of Braeandam 
House, 24 miles south by east of Callander. 
Fig. 2 (Reg. No. ™/499), on roadside, south-west of Muir 
Plantation, 34 miles south by east of Callander. 
Horizon.— Lower Old Red Sandstone. In greenish-grey 
flags and thin-bedded sandstones—in horizon “C” of section 
given by Messrs Jack and Etheridge (loc. cvt., p. 220). 
Before finally leaving this subject, attention might be called 
to certain fossils figured and described by Stur under the 
name of Lessonia bohemica in his memoir “ Die Silur- Flora 
der Etage H-h, in Béhmen,”! which seem to be very closely 
related to Arthrostigma. gracile, if not identical with it; but 
one cannot speak with any certainty from an examination of 
his figures and descriptions, as Stur’s examples do not seem to 
have been well preserved. Some of the other plants he figures 
from this horizon also seem ta be identical with some of our 
1 Sitzb. d. k, Akad. Wissensch., Abth. i., Band lxxxiv., Juli-heft, Jahrgang 
1881, p. 330. 
