924 



As regards duralion of life, the sand-slrand formation includes 

 anniials (Cakile, Alriplex) and perennials. The latter may be 

 »spot-bound« (sedentary) forms (Mertensia, Glijceria distans, Matri- 

 caria), or sucli as wander by means of surface runners (Agrostis 

 stolonifera, Potentilla anserina), or by subterrean stolons (Honckemja, 

 Elymus, Agropyriini, Carex incurva). The anatomicai structure of 

 most of the species has been investigated by different botanists, espe- 

 cially by E. Warming (1897). The leaves oi Honckenya, Mertensia, 

 Matricaria, Atriplex, Cakile and Cochlearia are thick and sncculcnt; 

 tliose of the grasses are to sonie extent xerophytic; Potentilla an- 

 serina is provided with felted hairs on the lower surface, while the 

 leaves of Cerastinm tetrandnm, besides being somewhat succulent, 

 have glandular hairs. 



Mosses and lichens do not appear in this formation. 



Examples: 



1. Sandy strand at tlie head of Trangisvaagfj ord, Sy- 

 der 6. (Honckenya association). Honckeiiya, Atriplex Babingtonli, Poten- 

 tilla anserina, Matricaria inodora phaeocephala grow scattered about 

 the beach south of the mouth of the streani. On the north side there 

 is a large beach-mound with a luxuriant vegetation of Honckenya, Ma- 

 tricaria, Atriplex, Agropyrum repens, Potentilla anserina, Haloscias scoti- 

 cum with Rumex obtusifolius and R. doraestiens here and there. The 

 beach itself is alniost barren, but isolaled piants of species of the 

 mound may occur, witli the exceplion of Haloscias and the Rumices. 



2. The beach outside ofthevalley at Kvalbo, Syder o. 

 (Honckenya association). Here we have a large naked sand-flat, but to- 

 wards the sea on a small beach-mound with stones, Honckenya and Ca- 

 kile try to maintain existence. 



3. Beach towards the head of Bordovig, l^ordo^ (Hon- 

 ckenya association, Atriplex facies). Atriplex Babingtonii grows in abun- 

 dance, with some Agrostis stolonifera with runners and Glyceria distans. 



4. The head of the in let near Midvaag,Vaag6, is a smooth, 

 flat sandy beach, the greater part of which is left dry at low-water. 

 Above that part which may be flooded by the sea at high-water, there is 

 a sand-bank formation (Elymns association) in that the wind has heaped 

 up the sand in little mounds, which are covered by Poa pratensis, Agro- 

 pyrum repens, Agrostis stolonifera and Potentilla anserina, mixed with 

 Elymus, Honckenya and Trifolium repens; the Agrostis also extends 

 seawards, and spreading with its long runners forms a luxuriant growth 

 on the bare sand. 



5. The mouth ofthe stream at Sandevaag, Vaago. Here 

 there is an expanse of sand and gravel with: Potentilla anserina, Hon- 

 ekenj'^a, Poa pratensis and Agrostis stolonifera, together with a few re- 

 presentatives of a number of species which have no doubt been carried 

 thitlier by the stream. 



^ On the northern islands (Nordreoer) there are very few sand-strands. 



