890 DR R. KIDSTON AND PROF. W. H. LANG ON OLD RED SANDSTONE PLANTS 
peaty matrix interrupted by irregular sandy layers. One block including the whole 
thickness of this bed was divided into four by horizontal planes, and the distribution 
of the plants followed in vertical sections of the. four portions. The peat of the 
lowest quarter of the bed contrasts sharply with the underlying sandy band in the 
absence of inorganic constituents. It has a peaty matrix with spores and fragments 
of plant-tissues arid, embedded in this, fairly well-preserved rhizomes, stems, and 
sporangia of Hornea ■ The sections studied show a practically pure Hornea peat 
with a very occasional stem that may belong to Rhynia. The division of Bed B 
above this shows a sandy matrix enclosing remains of Hornea and Asteroxylon, 
and overlying this a Hornea peat similar to that just described. The succeeding 
region has the peat much interrupted and mixed with sand ; the plant-remains are 
Hornea and Asteroxylon. The uppermost region of B 6 shows the same mixture of 
peat and sand ; the plants are Hornea , Asteroxylon, and Rhynia major. 
It is characteristic of Bed B 6, in contrast to A*l, that the peat is more 
interrupted by irregular sandy layers. The preservation of the plant-remains also is 
different, their tissues tending to become amorphous and yellow. The indications of 
accumulation of the peat by growth in situ of the vascular plants are less definite 
than in the case of the beds below ; the appearances are equally consistent with the 
view that the plant-remains might have been carried a short distance from adjacent 
growths of the plants. 
Above Bed B 6 came the second definite bed of fine siliceous sandstone (C) ; this 
was not examined in detail, owing to the obvious absence of plant-remains. 
The succeeding three and a half feet of the chert-bed in the section from Trench 
No. 1 contained, so far as we have observed, only Rhynia major. The main peaty 
beds are separated by sandy layers, and similar more irregular bands of dark sandy 
matrix interrupt the thicker masses of peat. This composition is well illustrated by 
the block from Bed E 10 that was represented natural size in Part I, fig. 1* 
The condition of preservation of the remains of Rhynia major may be noted 
very briefly, taking the beds in order. In Bed D the peaty mass is yellow and 
almost amorphous, only a few of the stems showing recognisable structure. In 
contrast to this type of preservation the stems in Bed E, which are often of large 
size, retain their cellular structure, although they may be more or less decayed and 
broken down. Rhizomes of Rhynia major have been found in this bed. In the 
lower portion of the following bed (F 116) the peat is composed of greatly altered 
plant-remains, which are shown to be Rhynia major by a few recognisable stems ; 
the general condition of this bed is similar to that of Bed I). An isolated tracheide 
of Asteroxylon was found in the matrix. In the upper portion (F 11a) the stems in 
various conditions of decay retain the cellular structure in the more usual way ; 
some resemble rhizomes, although rhizoids have not been seen. Beds G 12 and H 13 
contained more or less decayed stems of R. major, sometimes associated with 
* This block of the chert is preserved in the British Museum (Natural History). 
