VEGETATION OF BLAKENEY POINT. 
521 
has already been emphasised more than once, and a brief 
consideration of Statice binervosa will serve to illustrate the 
second. 
As described above, this plant is in general confined to a 
zone corresponding with the flanks of the laterals. On the 
main bank it is only found sparsely near the crest where the 
bank is very broad and consequently less mobile. It is also 
present on the slopes of the main bank, where a condition of 
stability comparable to that of the laterals is brought about by 
the presence of dunes situate on the seaward face. "A ith 
increase of fixity comes an acceleration in the rate of soil 
accretion, and this favours the growth of the Statice until the 
colonisation and spread of other plants brings in the factor 
of competition. These, although unable to establish themselves 
on the bare shingle, can successfully compete with the Statice 
immediately a shallow soil has been formed. It would seem 
that the condition of the fifth bank of the Marams series, where 
the “ Binervosa ” zone extends completely over the crest, is a 
condition in which the normal accretion of soil has been delayed. 
The arrival of the crest flora marks the beginning of a struggle 
in which, by the centrifugal extension of the turf, the “ Biner- 
vosa ” zone is driven further and further towards the sides (the 
places of slowest accretion), till finally it is narrowed to the 
merest line, or even disappears entirely. Evidence for such a 
sequence of events is furnished by relict plants of Statice , 
which are distributed with some frequency towards the edges 
of the crest association ; also on one of the laterals (Marams 
bank No. 8), where a portion of the crest has been artificially 
denuded of the overlying soil, we find Statice binervosa in 
some considerable amount. The very narrow zone of Statice 
on the intermediate lateral (“Yankee” bank) described above 
is no doubt related to instability, but whether this zone in the 
normal sequence of events spreads to the top of the bank before 
conditions for establishment have become adverse by the 
thickening up of the crest flora is open to considerable doubt. 
A striking feature of the relict Statices on the crest is that 
their average height and general vigour is considerably in excess 
