^{page 338 note 1} Mr. David Forbes says that “many beds, for instance the Gault, contain more iron than those Which are now red, though they may be grey or blue.”

^{page 338 note 2} In the form of bisulphide and carbonate. I have found iron pyrites in shales in Nidderdale, and bands and nodular beds of clay ironstone in many places.

^{page 339 note 1} Ramsay. Pretriassic Red Rocks. Proc. Geol. Soc., vol. xxvii., p. 246.

^{page 340 note 1} “The fish of the Marl Slate have generically strong affinities with those of Carboniferous age, some of which were undoubtedly truly marine, while others certainly penetrated shallow lagoons bordered by peaty flats.” Ramsay, Quart. Journ. Geol. Soc., vol. xxvii., p. 248.

^{page 340 note 2} Quart. Journ. Geol. Soc., vol. xxv., p. 291.

^{page 341 note 1} Quart. Journ. Geol. Soc., vol. xxv., p. 295.

^{page 342 note 1} Mems. of the Geol. Surv. of Engand and Wales.