272 Revieirs — Yorks/u're Geological Society. 



mode of origin of the several strata, defining their methods of 

 deposition and their properties. These strata are successively 

 arranged (from below upwards) in a long table (pages 16-21), with 

 (1) their local names; (2) their original constituents, and their 

 included animals and plants; (3) the mode of their formation as 

 deposits ; (4) the changes that have taken place in them since their 

 deposition; (5) their present properties and uses; ((5) their thick- 

 nesses. Thus, taking a series of Mr. Holgate's results in order, it is 

 pointed out that there is indication of (1) a beach; then (2) of dry 

 land of fine siliceous loam : (3) sinking land (with spores, fish- 

 remains, and trees) ; (4) land still sinking, and the deposit becoming 

 coarser, with the water almost motionless, away from the force of 

 the stream ; (5) centre of the stream, water flowing more quickly ; 



(6) direction of river still changing, water with quickening speed ; 



(7) ripple-marks at top, stream changing course and leaving ripple- 

 marks dry ; (8) stream again, over dried sandstone, depositing fine 

 white sand, which takes casts of ripple-marks below ; (9) centre of 

 stream now at some distance, and water moving gently; (10) water 

 more rapid; (11) water very slow; mud with Anthracosiee, fish- 

 scales and water-plants; (12) stream quickening, and so on, with 

 ever variable conditions of muds, sands, and coals, with or without 

 Fishes, Anthracosise, Lepidostrobi, Stigmaria^, Ferns, Calaniites, etc. 

 The salt and mineral waters are referred to ; the seat-earths or 

 fire-clays with their included roots and rootlets, are especially' noticed 

 (pp. 11-13), with their relation to the trees and plants once rooted 

 in them, and to the coal-beds overlying them. The shales, including 

 the blue, brown, and grey " binds," and the ironstone nodules, some 

 of which yield the " best Yorkshire iron," are also described, both 

 in the Table and at pages 13 and 14. 



The evidences of the growth of land and its replacement by water, 

 at this area, usually with river-currents, but once at least forming a 

 lake, with mud full of fishes and molluscs, are interesting, and 

 apparently very judiciously worked out. The chemical action in 

 dissolving and redepositing mineral-salts, and forming concretions 

 and definite nodules are noticed ; as well as the effects of lateral 

 thrusts and slidings. Lastly, the appreciations and uses of the 

 several beds, and their measured thicknesses, render this memoir 

 very valuable both to the practical people of Leeds and to geologists 

 in general. 



III. C. E. De Ranee continues his important researches, with the 

 other members of the Underground Water Committee of the British 

 Association, and here treats of the underground waters in Lincoln- 

 shire, as proved l)y borings at Gainsborough, Worksop, Horncastle 

 (tapping at Woodhall Salim Spring and as shown in the Appendix, 

 pp. 35-51) by the supply from wells and borings in the several 

 geological series of strata, there being about 15 water-bearing 

 horizons, half of which are regarded as good for a public water- 

 supply. 



IV. G. E. Vine supplies "Notes on some new little-known Eocene 

 Polyzoa," pp: 52-61, mostly from Fareham in Hampshire. The 



