428 ME. s. s. BrcKMAX ox [vol. Ixxviii, 



Oolite are tliin deposits, averaging about a foot or so. but the 

 Garantiana deposit is a thick one — running u^) to 40 or 50 feet, 

 perhaps more. The paucity of fossils accounts for such horizons 

 as there may be not being followed out in the different quarries of 

 Building-Stone, for these quarries may be really on various levels — 

 if so, the thickness would be much greater. Therefore, a sm'mise 

 of a possible 20-foot deposit for the original White Bed is not 

 necessarily a gross overestimate. 



It is interesting to note that these lithographic -stone beds of the 

 Yeovilian of AVatton Cliff and of the late Bajocian of Burton 

 Bradstock have a srreat likeness to the Continental strata termed 

 White Jura, diphya-k?Cik or Alpenkalk, which form so conspi- 

 cuous a feature of the ITpper Jurassic over wide areas. It has, 

 before now, been claimed for this country that its special geological 

 interest lies in the fact that, small though its area be, yet it con- 

 tains strata so fully representative as regards all the different dates 

 and all the different structures. Yet it is correct, I think, to say 

 that before the date of my discovery of the lithographic stone of 

 Burton, it showed nothing to compare with strata laid down under 

 those conditions which produced the Alpenkalk. Xow. however, 

 the Watton Cliff discovery adds another representative of such 

 conditions — a deposit made at a still earlier date : so it is now 

 unnecessary to travel outside England to obtain samples of strata 

 like those of the Alpenkalk. And there will be this additional 

 interest attached to them, that these beds of Watton Cliff and 

 Burton indicate Alpenkalk conditions of deposition prevailing 

 in Western Europe long prior to the date when they held good in 

 Cent]-al Em-ope.^ How long these conditions endm*ed in the 

 English cases, and what respective thicknesses of strata were laid 

 down, can only be matters of surmise ; for penecontempoi-aneous 

 erosion has removed so much, and caiue near to removing all. How 

 wide an area was occupied by such deposits is also matter for 

 surmise — they may have spread far over the area now occupied 

 by the English Channel. Some parts of the deposits may now 

 lie buried beneath its waters, other parts of them have certainly 

 been destroyed by those waters. Only a very few cubic yards of 

 deposit in the Burton case are now left available for investigation. 

 In the case of the earlier deposit, there may be a good deal more. 

 There is certainly not much in Watton Hill itself : for the bed is 

 cut off on the south by the Watton Fault, and on the west, north, 

 and east by the landward slope. There is, perhaps, no more than 

 an area of some 250 to 300 square yards preserved. But this ^Tiite 

 Bed has been detected in Shipton Long Lane. Bothenhampton — say, 

 about three-quarters of a mile inland from the east-and-west line 

 of Evpe — and there is a possibility that it can be found fai-ther 

 inland, as around Allington Hill. 



^ Mr. J. "W. Tutcher rightly dra-vrs my attention to the Sun-Bed in the 

 "White Lias of the Eadstock-Bristol district as being an earlier deposit of 

 similar character. Therefore in the South-West of England there was a 

 threefold repetition of this kind of rock. 



