_ primaeva.

_Lepidodendron_ dichotomum, et elegans, et Serlii, et Sternbergii, et
majus.

_Neuropteris_ acutifolia, et angustifolia, et flexuosa, et macrophylla,
et oblongata.

_Pecopteris_ abbreviata, et arborescens, et cristata, et dentata, et
Serlii.

_Sigillaria_ contracta, et elongata, et mammillaris, et ornata, et
reniformis.

_Sphenophyllum_ fimbriatum, et Schlotheimii, et truncatum.

_Sphenopteris_ Hibbertii, et macilenta.

_Stigmaria_ ficoides.

_Ulodendron_ Lindleyanum, et Lucasii.

The same variations in thickness as well as "faults" which have been
detected in the lower coal seams, occur in the middle measures, although
they do not in any case assume the same magnitude as the "Horse" in the
Coleford High Delf.

The heart of the Forest basin is well defined by its forming a slightly
varied plateau, containing the inferior and comparatively unimportant
seams of Woor Green coal, situated of course nearer to the surface than
the other veins, but as yet only sparingly worked, and not accurately
defined in its outcrop. The highest elevations in this portion of the
district are:--Surridge, 658 feet; Speech-house, 581 feet; St. Paul's,
Park End, 270 feet. The combined vertical thickness of the entire
formation, descending from the top surface to the old red sandstone, is
calculated by Mr. D. Williams at 2,765 feet, an opinion which is
corroborated by Mr. Atkinson's highly interesting sections based on his
practical acquaintance with the mining operations of the Forest.

Mr. Mushet obtained by analysis the following percentage of carbon in the
various descriptions of coal, viz.:--

Lowery Delf 62.
Coleford High Delf 63.72, 63.61, and 60.96.
Churchway 60.33 and 64.135.
Rockey 61.735.
Starkey 61.53.
Park End Little Delf 58.15.
Smith Coal 63.36.

None of these sorts of coal emit "fire-damp" in their natural
condition--a fact which adds so much to the safety of the pits; but
"choke-damp" is very prevalent.

The sandstone matrix of these coal-beds constitutes the grey and
buff-coloured rock so well known in the neighbourhood of the Forest as a
valuable building material, as well as for ornamental stonework.
Although for many years past it has been generally preferred to the
gritstone of the district, and is commonly met with in the b