rill'. SI- A-coAsr 



37 



There are also freiiuent sea-mists, which 

 may be dislinjjuished in tliis connection from 

 llie normal landward bree/es, since they do 

 not po»e-is much force, lull are characterized 

 by tlieir saturated condition. To these sea- 

 mists may largely bo attributed the hij^h per- 

 cent.nije of saline matter in the coastal sands, 

 shin.tjles. and salt marshes. Freiiuenlly also 

 sand storms are set up which have several 

 dilTerent elTects, such as the buryin^j of the 

 plants in sand, and the erosion by sand bl.ist 

 of those that are exposed. 



The waves also are powerful factors upon 

 the se.i-coast, exposini; plants to destruction 

 by the erosion of the coast. They also, in the 

 case of land to the leeward of dunes orshinijle, 

 have a beneficial elTecl by makinjf the condi- 

 tions saline. It is usually when there are 

 jjales that such occurrences take place. Thus 

 many factors contribute to the exposure of the 

 sea-coast. 



Erosion of the Coast. —One of the most 

 marked features of the present conditions so 

 far as the sea-coast is concerned is the erosion 

 of certain portions of the east and south coasts, 

 and to a far less degree of the west and north 

 coasts. 



Whilst there has been accretion or addition 

 to the coast in some areas erosion has been 

 ijointf on from time immemorial. .So \o\\y; 

 ajfo as the Roman period the Wash area has 

 been protected by banks in order to prevent 

 the farther advance of the sea. 



The sea margin is in fact continually chang- 

 ing. Generally speaking, however, a dis- 

 tinct ditTerenci^ exists between the west and 

 north coasts and the south and east coasts. 

 .Along the former there has been little destruc- 

 tion, and some addition, whilst on the latter 

 there has been almost generally a depletion of 

 the l.ind, with some exceptions. 



This is due to the fact that the older and 

 harder rocks are mainly found on the west 

 and north, whilst the newer and less resistant 

 rocks are found on the east and south. The 

 occurrence of hard rocks, however, such as the 

 chalk, locally, on the east and south coast, 

 as in Vorks, Norfolk, and Sussex, causes the 

 coast to preserve its contour intact, whilst 

 alternating soft bands, often where river 

 estuaries occur, are the areas where the coast 

 has been destroyed. .Along the e.-ist coast, 

 however, there is adrift of shingle southwards 

 to the Thames, so that some parts are pre- 

 served, or there may even be some accretion, 

 as at Blakeney and Lowestoft, and along the 

 Essex coast. 



West and East Coasts.— .As one passes from 

 the west of England to the east one is struck 

 by one important feature at least, apart from 



the dilVerence in the character of the coast, the 

 one rocky and elevated, the other llat. Kor 

 owing to the beni'ficeiit inllui'nee uf the 

 .\tl.intic Drift, which Hows to the west of 

 Ireland, and is fell in the .St. (ii'orge's (.'han- 

 nel, the temperature of the w<'st coast is much 

 higher than that on the east coast. This of 

 course makes the west co.-ist n)uch moister or 

 more humid. The hills are nearer I he west 

 than the east coast, hence the rainfall i> again 

 much heavier in the west than the east. 



On the east coast the clim.-ite is cold; winds 

 reaching the coast from thi' .Atlantic are al- 

 ready deprived of iheir moisture, and the 

 easterly winds from the Continent are dry. 

 The east is much drier as a whole, iln-n-fore, 

 and there is much less rain. 



In South-west Ireland the lempirature in 

 winter is like that of the Medilerraman. Tlu' 

 coldest area is in Central England northwards 

 to Scotland. The rockiness of the west and 

 south coast is another factor. Hence we have 

 on the west coast rupestral plants such as 

 Welsh Poppy, Thrift, and Scurvy Grass, on 

 the muddy sandy east coasts Sea Lavender, 

 Se.a Kale, Saltwort, &c. 



.All these factors — higher temperature, more 

 humid conditions, and a rocky substratum — 

 cause the western plants to differ from the 

 eastern, as may be illustrated by lists of plants 

 from each. The same applies largely to the 

 north and south coasts. The western plants 

 are .Atlantic types, the i-asti-rn GiTmanic. 



The Limitations of Seaside Vegetation.— 

 There are one nr two featiiro of mariliiiie 

 regions, so far as the British Isles are con- 

 cerned, which influence the vegetation they 

 support that ought to be pointed out, as they 

 are peculiar to this type. In the first place, 

 as briefly mentioned, the coastal border is near 

 the .sea-level. The temperature therefore is 

 more or less unilorm, and were it not that 

 there is a marked dilTerence on the west to 

 that on the east, and relatively between that 

 on the north and south coasts, the eflect of 

 altitude would be negligible in this case, and 

 the sole influence upon temperature would be 

 owing to latitude. 



As a whole the altitude at which nuiritimc 

 plants grow, except a few inland types, ;is 

 Thrift, Sea Plantain, and Scurvy (ir.iss, varies 

 between I and icw ft., so that all the plants 

 are of the ascending type, though they do not 

 actually encroach upon other types owing to 

 the necessity of saline conditions in the soil 

 and the restriction of this to the sea bordiT. 

 .Another feature is the generally uniform aspect 

 of plants on each of tin- coasts north and 

 south, cast and wi-sl. Each .seaboard is more 

 or less restricted to certain cla.sscs of wind, 



