— ———— 
13 
80 great a break in the animal life, although, in other areas, there 
are better evidences of a transition state.* 
The Lower London Tertiaries (see map) include the Thanet 
Sands, Woolwich and Reading Beds, and the Oldhaven Beds :-— 
“The Thanet Beds occur only in the south-eastern part of the 
London Basin, beginning from the neighbourhood of Leatherhead, 
where they thin out. Thence eastward they gradually thicken and 
take up more surface, but nowhere do they form a large tract. 
They are confined to the eastern part of Surrey, the southern part 
of Essex and Kent, throughout which last county they always 
overlie the Chalk, attaining their greatest development in the 
Rastern Division. 
“The Woolwich and Reading Beds occur throughout the 
London Basin, at least it is but a very few spots in West Kent 
where the overlying Series has cut them off, and rest on the Chalk 
(in the absence of the Thanet Beds) over the greater part of the 
London Basin. Their outcrop is very narrow, especially where 
their dip is high, as along the northern flank of the Hog’s Back. 
A multitude of outliers proves the former extension of this 
thin Series. 
‘The Oldhaven Beds are sti!l more local than the lowest 
division of the Lower London Tertiaries, occurring only on the 
south from Croydon eastward, that is to say, at the most eastern 
part of Surrey and through Kent ; and in this small range they are 
sometimes absent. Although of little thickness this series forms 
some comparatively broad tracks in the north-western corner of 
Kent, but in East Kent the outcrop is very narrow.” + 
The Thanet sands, the first of the tertiary series, have, however, 
but a limited extent near Croydon; they are seen in the railway- 
cutting, near Coombe Lane, and in the large pit beyond, at Duppas 
Hill, Croham Hurst, and probably'the Waldrons, according to Mr. 
Whitaker, being a portion of the same beds which extend from 
Ashstead to the Isle of Thanet (hence their name), and where they 
attain their greatest thickness. Richborough Castle, the site of the 
Roman Ritupium, at the entrance of the Stour, and the Reculvers, 
near the ancient Regulbium, which guarded the north entrance of 
* With regard to the relations of the Cretaceous and Tertiary periods to each 
other, Dr. Hayden observes, ‘There is no proof so far as I have observed in all the 
Western County, of a true non-conformity between the Cretaceous and Tertiary beds, 
and no evidence of any change in sediments or any catastrophe sufficient to account for 
the sudden and complete destruction of organic life at the close of the Cretaceous 
period.”—Geol. Surv. Colorado, 1869, p. 169. 
Prof. Cope in alluding to the transition series of the Rocky Mountain region, says, 
“There is, then, no alternative but to accept the result, that a Tertiary flora was con- 
temporaneous with a Cretaceous fauna, establishing an uninterrupted succession of life 
across what is generally regarded as one of the greatest breaks in geologic time.”—Bull. 
Geol. Surv., No. ii., p. 16. 4 
This conclusion does not appear to exactly conform to facts, according to Prof. 
Lesquereux ; at least on the point of view of vegetable paleontology.—Colorado Report, 
1873, p. 372. 
+ Whitaker, Mem. Geol. Surv., vol. iv., p. 9. 
