1909] 



OLSSON-SEFFER— VEGETATION ON SEA SHORES 



97 



ber, 1901, while the lowest was 2?i near Mariehamn, Finland, in 



September, 1896. The 



i8?4C. 



average 



of these sixty observations was 



The soil temperature on the middle beach is already much higher, 

 as following data will show. The observations were made at the 

 same time and in the same place as those mentioned in Table I. 

 The distance from the water was 6 . 5 m and the sand pure quartz of 

 medium size and yellow color. 



TABLE III 



2 cm. 



I 



2 



3 

 4 



5 

 6 



7 



22 .6 

 19. 1 



23-4 

 20.1 



18.4 



16.9 



19.8 



5 cm. 



20.I 

 16.7 

 21.3 

 18.5 

 16.9 



15-2 



17-3 



10 cm. 



17 



18 



17 

 is 



15 



8 



9 



9 



o 



6 



7 

 S 



20 cm. 





14. 1 

 12 .7 



15-3 

 13-9 



12 .7 

 12 .6 

 I3.8 



50 cm. 



12 .6 

 12. I 



13-3 

 12.7 



12.2 



11. 9 

 12.9 



The vegetation consisted in i and 3 of an open community of the following 

 constituents: 



Facies: Leontodon autumnale, copious. 



Secondary: Festuca ' rubra armaria, subcopious, Agrostis vulgaris, sub- 

 copious, Plantago maritima, gregarious, Erythraea litoralis, sparse. 



In 2 Erythraea was scattered about in patches, between low shrubby Alnus 

 ghhnosa, solitary individuals of Elymus arenarius, and Rosa canine. 



In 4, 5, and 7 a J uncus Gerardi community occurred on the middle beach, 

 Wifll sparse Erythraea litoralis and Plantago maritima. In 6 Elymus arenarius 



Fes tuca rubra arenaria formed an open community. 



A parallel table to Table II shows the temperature conditions on 

 Ae middle beach at Fremantle, W. Australia. The sand was here 

 ne > c °nsisting of pure light-yellow quartz. Time and atmospheric 

 conditions as in II 



2 cm. 



TABLE IV 



5 cm. 



23 .4 

 25.8 



18.6 



21 .3 

 16.9 



10 cm 



22 .4 



24 .6 



18.3 

 19.6 



16. r 



20 cm. 



20.7 

 23.6 



16.5 

 17.2 



14.9 



50 cm 



18.4 

 20.0 



15.8 

 16.3 



14-4 



