§ 4. THE IGUANODON COUNTRY. 489 



mind, to the time when I was compelled by ill health to quit 

 the field of my early researches, I lost no opportunity of 

 obtaining data by which the problem might be solved, and 

 carefully examined the pebbles and boulders, and the fine 

 detritus as well as the coarser materials of which theWealden 

 beds are composed. 



My lamented friend, the late Mr. Bake well, kindly 

 afforded me his valuable aid in determining the nature of 

 the rocks whence the debris was derived ; but the materials 

 were too scanty to throw any satisfactory light upon the 

 inquiry. In my "Fossils of Tilgate Forest" a bed of 

 conglomerate, near Cuckfield, is described as containing 

 pebbles of white, yellow, pink, and mottled quartz, j asper, 

 flinty-slate, and indurated sandstone : and from this deposit 

 I expected to obtain more satisfactory information than 

 from the fine detritus of which the sands, sandstones, and 

 clays consist. But with the exception of small pebbles of rock 

 crystal,* the substances above mentioned comprise all the 

 transported minerals that have come under my observation. 

 The abundance of micaceous particles in many of the sands 

 and sandstones, and the prevalence of argillaceous and 

 arenaceous deposits, seem to indicate a region in which 

 were primary rocks, and strata of sandstone and clay ; for 

 the quartz pebbles, and the micaceous sands and clays, 

 may have been derived from decomposed granitic and felspa- 

 thic rocks. I have never seen any extraneous fossils either 

 in the Wealden or Chalk, with the exception of a rolled 

 fragment of coniferous wood, which, from its state of 

 mineralization, there is reason to conclude is from the 

 oolite.f 



* Small rock crystals are often found in the sandstone near Tun- 

 bridge Wells, and are cut and set in rings and brooches by the lapi- 

 daries of that town . 



f This specimen was found by my friend Henry Carr, Esq. C.E., 

 in a block of white chalk from a railway cutting near Epsom. See 



