( Read November 26 th . 1919). In a previous paper, published by this Society some ten years ago.† I described the 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 pits 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 present paper is concerned. Two lists of species occurring at Bond’s Main have been already published by Horwood‡ 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, Cambridge, were formed some years ago. partly by the Author and partly by Mr. I. Rogers. They include a number of species not hitherto recorded, as well as examples of many of the plants instanced by Horwood or Moysey or both observers. The horizon|| of the plants in question, is the roof of the Silkstone seam or between the Deep Hard and the Silkstone coals. The Silkstone seam occupies a considerably lower position in the Middle Coal …