VEGETATION OF SANDY SEASHORES 5 



been estimated that nine-tenths of the coast-line of the world 

 are fringed by sands. Sand-dunes which, as will be shown, are 

 largely built up by plants, extend for miles along many parts 

 of our shores, on the coast of Holland, and along the east 

 coast of the United States. To find plants in their natural 

 habitat, it is best to avoid the fashionable seaside resort, and 

 to spend a summer holiday in some primitive spot, if pos- 

 sible, away from esplanades, piers, bands, and trippers. The 

 following observations were made in a little village of North- 

 umberland where the sands stretched for miles and were 

 practically undisturbed. Walking on the sands, one soon 

 realised that there was an area with very few plants, owing to 

 the constant blowing about of the sand by the wind ; this may 

 be called the area of shifting sand. The two most common 

 plants of this belt were the Sea Rocket (Cakile maritima) and 

 the Saltwort (Salsola Kali}. The former is a cruciferous plant 

 with fleshy leaves and lilac flowers. The pods are worth noticing. 

 Each divides into two portions, a short lower and a long upper 

 segment. The upper portion falls off in the autumn, the seed 

 gets buried in the sand and germinates the following spring. 

 The leaves of the Saltwort are not only succulent, but prickly. 

 The plant is usually about six inches high, and bears minute 

 flowers in the axils of the upper leaves. In many places the 

 Sea Wheat-Grass (Triticum junceum) is the first plant to 

 establish itself on the drifting sand. This is shown in the 

 photograph by Dr. Pettybridge, who has investigated the Plant 

 associations of the Dublin district. The Sea Wheat-Grass is 

 seen in the foreground, and associated with it the Saltwort and 

 the Sea Purslane (Atriplex portulacoides) . This grass has creeping 

 underground stems (stolons), and these help to fix the loose sand. 

 Within the area of shifting sand comes a belt of sand in which 

 the wind has not free play, for certain grasses and other plants 

 have begun to bind the sand together, weaving it into a soil of 

 firmer texture than shifting sand can have. The Marram Grass 

 (Psamma arenaria) and the Sand-Lyme Grass (Elymus) are the 

 two species most commonly found. Both these grasses have long 

 rhizomes, which bind the sand as they spread in matted tufts. 

 The Marram may easily be distinguished from the Lyme Grass 



