Clare Island Survey — Marine Algae. 15 153 



to the fields ; on the mainland it is at times carted seven or eight miles inland. 

 In other localities, such as Old Head and Bartraw, the farmers are content 

 with drift-weed of a miscellaneous description. The drift is more valuable at 

 some seasons than others. At times it is composed almost entirely of semi- 

 decayed red weeds cast up from the shallow water, and at others there is a 

 certain amount of Laminaria, and occasionally Fucus. 



Black Wrack (Fucus vesiculosus and Ascophyllum nodosum) is systemati- 

 cally collected during February and March, where Laminaria is scarce. In 

 the rocky parts of Clew Bay, and in many localities on the open coast, it 

 grows freely on the rocks, though for a really large amount a flat shore is 

 essential. This is supplied in abundance in the inner part of the bay, and in 

 Achill Sound. Where rocks are present Fucus grows naturally, but where, 

 as is usually the case, the shore is composed of sand, the farmers set to work 

 to obtain a growth of Wrack by artificial means. Stones about a foot square 

 are disposed in rows a yard apart, with paths left between for carting. 

 Sporelings speedily appear on the stones, and during the course of a year 

 develop into good-sized plants. The following season the Wrack is cut. This 

 operation, which takes place in February and March, was observed by the 

 Survey party of Easter, 1910. The weed on cutting is built up in stacks 

 about six feet high, and after being tightened up with ropes is towed ashore 

 on the flood-tide, and bleached at high- water level. Here it is unpacked and 

 carted to the fields. 



The botanical features of the Fucus-farms are dealt with on p. 53. Owing 

 to the symmetrical arrangement of the stones, the artificial plots are at once 

 distinguishable from natural vegetation ; but when the weed is in its second 

 season and the plants inclined to overlap, the distinction might not strike the 

 eye of a casual observer. Plate V, fig. 2, gives a view of the plots. at 

 Darby's Point ; similar farms occur in other parts of Achill Sound, and in 

 Clew Bay they were noted at Murrisk. 



The " coral-sand" described on p. 71 should be referred to here, as it is 

 used for manuring in Connemara. Johnson and Hensman ('99) give the 

 analysis of a Ban try Bay sample, which shows that the sand consists of 

 about 80 per cent, of carbonate of lime. To this fact its. efficacy as a 

 fertilizer is attributed, and it is doubtless specially useful on the peaty 

 shores of W. Ireland. 



Recent Literature. 



The Composition of Seaweed and its use as Manure. Journ. Bd. Agr. 

 London, xvii, pp. 458-467 (September, 1910), p. 832 (January, 1911). Also 

 abridged as Leaflet No. 254. 



B.I, A. PBOC, vol. xxxi, U IS 



