267 



Preliminary Report of the Comonittee, consisting of Professor W. 

 C. Williamson, and Mr. Wm. Cash (Secretary), on the Flora of 

 the ' Halifax Hard Bed,^ Lotver Coal Measures. 



The present Report is on the fossil plant-remains, whiclL are found in a 

 singularly perfect state of preservation in a thin bed of impure coal in 

 the ' gannister ' series of Halifax and its neighbourhood, in the county 

 of York. 



Our observations relate to an examination of specimens from numerous 

 coal-pits situated on an area extending from the vicinity of Bradford on 

 the north to Sheffield and district on the south. 



Many of the pits in the district now indicated are no longer worked, 

 partly on account of the reduced price of coal of late years and partly 

 because the iron pyrites brought up in working the coal (which was 

 formerly sold for chemical purposes) has been superseded by the im- 

 portation of sulphur at a cheap rate from Italy and other countries. 



These influences have acted adversely upon your Committee, since 

 some of the best pits for the special ' coal balls ' in which the coal plants 

 are found have been closed. Still, we have to report the acquisition of a 

 goodly number of ' coal balls ' which await examination. Before their 

 contents can be properly studied they will have to be cut into thin slices 

 preparatory to microscopical investigation. Already we have prepared 

 upwards of one hundred microscopical slides for cai-eful study. 



Halifax appears, so far as our observations go, to be the centre of this 

 rich Carboniferous flora. The bed in which the fossils are found is 

 two feet three inches thick in the neighbourhood of Halifax, and consists 

 of an impure coal, which in many places is thickly studded with nodules, 

 or, as they are locally called, ' coal balls.' These are composed chiefly 

 of carbonate of lime, some carbonate of magnesia, along with smaller 

 quantities of oxide and sulphide of iron, sulphates of soda and potash, 

 and a little silica. These nodules contain imbedded rootlets, stems, 

 leaves, Lepidostrobi, spores, and occasionally the mycelium of fungi. 



The state of preservation of the fossils is very remarkable ; the tissues 

 of the plants are infiltrated with carbonate of lime and the cell- walls 

 are carbonised, so that in thin slices prepared for the microscope the 

 minutest details are clearly defined. 



The roof of the ' hai^d bed ' is a thin stratum of shale filled with the 

 flattened valves of a bivalve shell (Aviculopecfcen) ; above this is a bed of 

 shale with numerous calcareous nodules, coated and often impregnated 

 with iron pyrites, and containing fossil shells of the genera Aviculo- 

 pecten, Goniatites, Nautilus, Orthoceras, and others, a very prevalent 

 fossil being Goniatites Listen. The base of the bed is composed of 

 ' gannister,' and abounds in Stigmarian roots. 



In the northern part of our district around Bradford the * coal balls ' 

 are scarce, and so highly charged with iron pyrites that plant-remains 

 suitable for microscopical examination very rarely occur. The same 

 remark applies to Huddersfield, and in a somewhat less degree to the 

 southern area around Hazlehead and Shefiield. 



The three most prolific localities are situated at Sunny Bank, South- 

 owram, at Sugden Pit, Bradshaw, and near BUand, all of which are in 

 the immediate neighbourhood of Halifax, but unfortunately the two 



