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hood of Ellesmere have been supposed topossess characters peculiar to the sandstonein which they occur; and beds of gypsumare particularly noticed by the Freybergschool on account of the funnel-shapedhollows that appear in them. Some natu-ralists affirm that all coal-measures are de-posited in troughs and basins, and dip in-wards to a common point.

Strata occupying basins I have generallyobserved to be most disturbed where thebasins suddenly contract, as the coal-mea-sures of Pembrokeshire. Professor Rau-mer’s Memoir furnishes me with a similarexample at Flinsberg and Harrachsdorf inSilesia.

To conclude, then, let me ask, Where arock is stratified, is it necessarily boundedby parallel surfaces ? if so, let us hear nomore of mantle-shaped, saddle-shaped,shield-shaped, fan-shaped, basin-shaped,trough-shaped stratification.