102 
CHALK AND GREENSAND. 
2. The Chalk, —The traveller from Lon¬ 
don in any direction will find after passing 
the deep clays of the first cuttings on his 
road, a more open hilly district, sections in 
which display the dazzling whiteness of the 
chalk. The lower beds of this are sandy, 
and rest on an associated deposit called 
greensand, A few sea weeds and some 
portions of drift wood, yield all the know¬ 
ledge we obtain from the pure chalk, as to 
the state of contemporary vegetation. 
Nearly all its organisms indicate a deep sea 
with few^ islands. The lower sandy beds 
are, however, rich in accumulations of drift 
wood and sea-w^eed, with local deposits of 
plants, among which stems of Dracaena, 
cones, and fruits indicate the existence of 
pine and palm w^oods. 
3. I'he Wealden, —Our geological traveller 
will find on arriving at Swindon a narrow’ 
fossiliferous bed, w hich is the prolongation 
of deposits more largely developed in the 
South Eastern counties, consisting of dark 
clays and sands usually crowned with oak 
foliage, and bearing internal tokens of having 
been formed at the mouth of some vast 
