882 DR R. KIDSTON AND PROF. W. H. LANG ON OLD RED SANDSTONE PLANTS 
NEMATOPHYTON, Penhallow. 
1859. Prototaxites, Dawson, Quart. Journ. Geol. Soc., vol. xv, p. 484. 
1871. Nematoxylon , Dawson, Geol. Survey of Canada, “Fossil Plants of Devonian and Upper Silurian 
Formations,” p. 20. 
1872. Nematophycus, Carruthers, Monthly Micros. Journ., p. 172. 
1888. Nematophyton, Penhallow, Trans. Roy. Soc. Canada, vol. vi, section iv, p. 36. 
4. Nematophyton Taiti, n.sp., Kidston and Lang. 
The discovery in the Rhynie chert of a fragment of tissue, the structure of which 
agrees closely with that of plant-remains known from the Silurian and Devonian 
formations under the names Prototaxites , Nematoxylon, Nematophycus, or Nema- 
tophyton adds to the interest of the deposit. This small fragment only appears in 
two successive sections of a block from Bed A ff l ; it measures only 3x2 mm. The 
characteristic structure is, however, well shown, the tissue being composed of 
systems of wide and of narrow tubes ; the differences from the specimens on which other 
species have been founded are merely in details, such as those on which these species 
are distinguished. This .is, we believe, the first record of Nematophyton from the 
Old Red Sandstone of Scotland We have pleasure in naming this species Nema- 
tophyton Taiti, after Mr David Tait, who superintended the excavations at the 
Muir of Rhynie that resulted in the discovery of the silicified peat-bed in situ. 
We associate with this fragment, without giving it a separate name, another 
slightly larger portion of a plant which occurred at the same level in the same block, 
but was cut in two other sections of the series. This second fragment, which was 
only about 4 cm. distant from the fragment showing the typical structure of Nema- 
tophyton, is a portion of the peripheral region of a cylindrical structure. The 
structural differences it exhibits from the other fragment can reasonably be ex- 
plained on this ground. Though there is no proof of continuity, we feel justified 
in placing it with the first specimen under the same name. The two specimens will, 
however, be described apart, and the figures will enable the reader to form his own 
opinion as to their belonging to the same plant. 
If, as we beiieve, the second fragment shows the peripheral region of a plant 
the central portion of which had the typical Nematophyton structure, it is a welcome 
addition to our knowledge of this remarkable genus. It is in any case a portion 
of the peripheral region of a plant of a similar type of construction. 
The two specimens may now be described in detail, taking them in the order in 
which they are mentioned above. 
One of the two sections with the typical structure of Nematophyton is slightly 
larger than the other and shows the tissue better preserved. The irregular edges 
of the fragment are decomposed and covered with a granular mass that is possibly 
of bacterial origin. The greater part of the better section is shown magnified 50 
diameters in fig. 109. This figure shows that the wide tubes making up the bulk 
