:^50 
ON THE FOSSIL FLOKA OF THE SOLTHERN PORTION OF 
THE YORKSHIRE COALFIELD. 
Part II. — North Derbyshire. 
By the late E. A. Newell Arber, M.A., Sc.D., F.G.S., 
Trinity College Cambridge : L^niversity Demonstrator in 
Pala^obotany.* 
{Read Xoremher 26th. 1919). 
In a previous pa])er, ])ublished by this Society some ten years 
ago,f I described th^ fossil flora of the Middle and Lower Coal Measures 
in the extreme south of the Yorkshire Coalfield in Nottinghamshire 
and Derbyshire. In the present paper an account is given of the 
Middle Coal Measure flora of a region in Derbyshire further to the 
North, but lying to the South of Chesterfield. This district appears 
to be a comparatively poor collecting ground for fossil plants, with 
the exception of two i)its at Temple Normanton — Bond's Main and 
Grassmoor Collieries — which in recent years have become well known 
on account of the excellence of their fossil floras. It is with the plants 
collected at these localities that the j^resent paper is concerned. 
Two lists of species occurring at Bond's Main have been already 
published by HorwoodJ and by Dr. Moysey,§ and the former has also 
added a short list from Grassmoor Colliery. Further collections from 
both these localities, which are now in the Sedgwick Museum, Cam- 
bridge, were formed some years ago, })artly by the Author and j^artly 
by Mr. I. Rogers. They include a number of species not hitherto 
recorded, as well as examples of many of the jilants instanced by 
Horwood or Moysey or both observers. 
The horizon] I of the plants in question is the roof of the Silkstone 
seam or between the Deep Hard and the Silkstone coals. The Silkstone 
* [Owing to the author' .s deatli before this paper was revised, the 
responsibility for any error.s which it may contain rests with me. I 
have to acknowledge a grant from the Royal Society in aid of the 
preparation of this and other memoirs lAt by my husband in various 
stages of completion. — Agnes Arber.] 
t Arber (1910). 
t Horwood (1912). 
§ Moysey (1913). 
II [A later note by Dr. Arber indicates that he regarded the horizon 
as representing the clividing line between the ^Middle and Lower Coal 
Measures. — A. A.] 
