ARBER : FOSSIL FLORA OF SOUTH YORKSHIRE COAI.FIELD. 135 
Clay Cross, presented by Dr. Pegler to the British Museum (Nat. 
Hist.) in 1892. Mr. Horwoodi gives a list of these fossils. In 
these cases, however, the exact origin or horizon of the plants is 
unknown, though the Clay Cross fossils are for the most part 
from the Middle Coal Measures. 
^ THE FOSSIL FLORA. 
My friend, Dr. L. Moysey, F.G.S., of Nottingham, has for 
some years past devoted much attention to the palaeontology of 
that portion of the basin, which lies to the West and North-west 
of that town. He has obtained a large collection, chiefly derived 
from the clay-ironstone nodules, both of invertebrates and of 
fish and plant remains. The former are in course of description 
by Dr. Henry Woodward. Dr. Moysey has generously placed the 
fine series of fossil plants in his collection at my disposal for 
examination and description. For his kindness in this matter I 
owe him many thanks, and I am also indebted to him for oppor- 
tunities of visiting the chief localities, from which his collection 
has been derived. It should be also pointed out here that the 
excellence of many of the specimens in Dr. Moysey's collection 
is due to his ingenious method of splitting the ironstone nodules 
in natural planes, by the freezing method, which he has described 
in paper published in 1908.^ 
The southern extension of the Yorkshire Coalfield lies partly 
in North Derbyshire and partly in Nottinghamshire, the boundary 
between the counties being the river Erewash, which traverses 
the strike of the most southern portion of the field. Thus two 
localities, though only separated by a few hundred yards, may be 
in two different counties. 
The succession of coal seams in this district is given by Dr. 
Walcot Gibson,'^ in the recently published Survey Memoir, where 
a full account of the geology wiU be found. The majority of Dr. 
Moysey's specimens were derived from clay pits, the horizons of 
which may be regarded as approximately identical with that of 
the Top Hard Coal. A smaller number of specimens have also 
been obtained from between the Waterloo and the Ell and Deep 
I Horwood (07). 2 Moysey (08). 3 Gil.soii (08). 
