82 Scientific Proceedings, Royal Dublin Society. 



wliich these shores are subjected. All rouud the south and south-west coasts 

 Pelvetia cananiculatus, Fueus spiralis, Ascoplnjllum nodosum, Fiicus vesiculosus, 

 and Fucits serratus are general and abundant (only from the steeper cliffs at 

 Drumleck Point, from the sea-faces of the Needles, and from Lion's Head, 

 was Pelvetia absent). In the shallow bays of Broad Strand and Glenaveena 

 F. spiralis, var. platycarpus, replaces the species. Povphyra umbilicalis is also 

 general, and usually forms a well-mai-ked zone on the cliffs above Pelvetia ; 

 on the flat shores of Broad Strand it extends almost tluoughout the whole 

 neap-range. It is most common in the Pelvetia belt, and just below it, but 

 it occasionally grows in large patches above Pelvetia, and where fresh water 

 flows is frequently associated with Enteromorpha intestinalis. These are algae 

 of sheltered and semi-exposed coasts. 



Except during easterly gales, which, as a rule, only occur in the spring, 

 when the spray sometimes rises as high as the Cliff-walk, there is very 

 little wave-action along the east coast, and the cliff-faces are seldom wet 

 with sea-water for more than a few feet above high-water mark. 



At Casana, one of the few accessible spots on this coast, the following 

 algae were noted : — Porphyra umbiUcalis with the narrow form var. linearis 

 in two zones on the large boulders lying just above spring-tide level, 

 P. umbilicalis being nearer the sea and extending down into a belt of Fucus, 

 on which Rhodymenia palmata was growing epiphytically. Mr. A. D. Cotton 

 considers that this Fucus comes near F. vesiculosus, var. evesiculosus, of 

 exposed coasts, but that it indicates much less exposure than there is on the 

 south shore of Glare Island. Pelvetia cananiculatus only occurred here and 

 there as odd plants in the most sheltered, spots amongst the boulders. 

 Ascophyllum nodosum was not seen at any of the places examined on tliis 

 coast, though it is general and abundant along the greater part of tlie north 

 coast. On the limestone area at Balscadden Bay a narrow form of Fucus 

 vesiculosus without bladders occurs above Fucus serratus, the last being 

 exceedingly abundant. Ascophyllum nodosum is absent from the limestone, 

 but occurs on the silicious rocks on the opposite side of the bay. 



Previous work. — From a study of all the available literature it would seem 

 that the lichens of the sea-shore have been the subject of very little 

 investigation. Since the publication of Nylander's account of the Lichens of 

 Pornie in 1861 (20), which was one of the first dealing with a maritime area, 

 Weddell's paper on the Lichens of I'lle d'Yeu (30) is the most important 

 contribution that has been made on the subject. Weddell's paper deals 

 chiefly with the systematic side of the question, though ecological factors are 

 not entirely overlooked, as he gives copious notes containing much valuable 

 and interesting information about tlie habitat and range of many of the 



