Clare Island Survey — Marine Algae. 15 87 



former, as already indicated, is clothed with V. coronata, Rhizoclonium, and 

 Enteromorpha ; but many other algae occur, all the species mentioned for the 

 salt-marsh Rhizoclonium association (p. 79) being noted. Beautiful dark 

 patches of Capsosiphon were found in May on stones at half-tide level. 

 V. coronata disappears as one nears the sea ; but another species with 

 filaments 2-3 inches long, only found sterile, becomes frequent in pools. 

 A fine Microcoleus association (see p. 63) is also present in the sand and 

 sandy mud found between the loamy ground and the stone-covered banks. 



With the appearance of stones and boulders the Fucaceae vegetation 

 sets in. At first it consists of pure F. ccranoides, but F. vcsiculosus soon 

 follows, appearing first on the uppermost boulders (where it would obviously 

 receive the least amount of fresh water), and gradually increasing till at the 

 embouchure the two species occur in equal proportions. A second plant- 

 association is represented on the stones, namely — Fnteromorpha intcstinalis. 

 This exists as a pure, luxuriant growth in the bed of the stream. In a 

 modified form, it ascends the banks under the Fucus-covering, and in spots 

 forms a green band above it. 



F. ceranoides accompanies the river on to the fiat sandy beach, and is found 

 on the rocks to the east of the main stream, where it is doubtless under the 

 influence of the fresh water. The association of Porphyra, which occurs below 

 (p. 58), must also receive a certain amount of brackish water. 



Bellacragher Bay Streams. 



The streams which descend from the high hills and peat bogs of Curraun 

 Achill seldom if ever dry up, though the amount of water brought down 

 varies greatly. A well-marked vegetation is present at the outlets, which is quite 

 distinct from that of ordinary streams, and which is probably characteristic 

 of small mountain torrents. It consists of F. ceranoides, and a species of 

 Monostroma (No. 91, see p. 107), and does not appear to have been previously 

 described. As a rule there is a large deltoid mass of F. ceranoides, with a 

 smaller patch of Monostroma in the upper part ; but the physical nature of 

 the shore modifies the horizontal distribution of the algae, so the deltoid 

 form is often more or less lost. 



F. ccranoides shows first on the stones in the stream near the ordinary 

 high-water line ; and on descending the shore it spreads out laterally over 

 the flanks, and continues to low-water mark. Though a large portion remains 

 immersed all day in fresh-water, it is completely covered by each tide. The 

 plants fruit abundantly, but do not attain to so large a size as those found on 

 river-banks {e.g. Bunowen and Newport). 



