734 



cannot produce receptacles in this nnfavourable habitat. The Hi- 

 /rja7j//ja//a- association is so characteristic on exposed coasts, that 

 a luxuriant growth of this alga is a sure sign of the presence of 

 surf. It is an association particularly fitted for resisting the dashing 

 of the waves; the surf constantly washes over the association at 

 low tide, and the metre- long, phable, elastic receptacles of the 

 Himanthalia follow resistlessly the movement of the sea. Himan- 

 thalia cannot stand to be dry for any length of time; when found 



Fig. 155. The //ini<in(/Ki/ia-association. liesides piants with receptacles, youiiK' piants are secii. The siib- 

 vegetatlon consists of Gigartina mamillosa, l'olysiphonia urceolata, Acrosiplwiiia, Comllina, etc. The illustra- 

 tion is taken from Midvaag. (F. B. phot.) 



on a sheltered coast, where however it is rare, it always grows 

 sublittorally in low water and often has another appearance. The 

 receptacles are uneven, somelimes inflated, and the colour of the 

 plant becomes a lighter yellowish-brown. 



As a subvegetation to the HimanthaliQ -associniion, Gigartina 

 mamillosa, Acrosiphonia, Polysiphonia urceolata, and others often oc- 

 cur besides Corallina (see fig. 155). Elachista scutiilata has occa- 

 sionally been found growing on the receptacles, and on the old piants 

 a great many epiphytes are sheltered, especially species oi Edocarpiis 

 e. g. E. fasciciilatus, E. Himksiæ, E. iomenlosus and E. litoralis, species 



