l06 Scientific Proceedings, Royal Dublin Society. 



scopiilonim more than 50 feet above sea-level. Eounding the Point one finds 

 on the eastern side the Lichinas forming two zones at much lower levels ou 

 the cliff-face, a narrow baud of L. confinis running along the upper line of 

 the Verrnvarla nmuraheli ; while below V. maura, L.pygmaca forms a marked 

 band about 10 inches in depth. At the same level as L. iiygmaea on this 

 cliff-face, but nearer the land and more in shelter, Catanella ojmntia grows in 

 an equally wide band, which at a little distance looks like a continuation of 

 the L. 'pygmaea zone. This alga, which is abundant round the Howth 

 coasts as an undergrowth of Peloetia cananiculatus and Fucus spiralis, forms in 

 shade, where these species are absent, a band on the steeper cliffs below 

 V. maura. Ou tlie Needles and ou Drumleck Point Catanella often grows 

 in close proximity to L. pygmaea ; the latter, is however, always found more 

 towards the open sea and is easily distinguished by the hard, crisp feel of the 

 growth, Catanella being soft and yielding to the touch. 



On the inner face of Needles Lichina confiiiis forms a band 4-5 inches 

 wide above V. maura and between it and a band of Placodium lobutatum 

 3 feet wide. On the western face of the pinnacles botli Lichinas occur in 

 tlieir relative positions ; but from the outer and exposed faces both species 

 are absent. 



Ou the sloping cliffs behind the Needles the zonal distribution of the two 

 species is very well seeu, the zone of L. pygynaea being 3 feet wide and 

 ruuuiug along the cliffs for 30 to 40 yards. Below the cliffs on the rocky 

 foreshore L. pygmaea also occurs and is distributed throughout the whole 

 neap-range, the most vigorous patciies being found near low water on the 

 rather higher parts of the rocks which project up above a close mat of 

 Laurencia pinnatiflda and Gigarlina mamillosa. 



On the sheltered shore below Earlscliffe L. pygmaea is very scarce and 

 the Lichina confinis growth is thin and occurs lower on the shore thau usual, 

 in some places being seen amongst the Pelvetias; but good growths of both 

 species are found on the high rougli rocks and boulders that lie about the 

 middle of the Broad Strand, L. pygmaea growing most vigorously on the 

 steep sea faces and western sides of tlie higher boulders where it meets the 

 wind and is splashed by the waves, forming patches of considerable size 

 around the attachments of Pelvetia and Fucus spiralis, Lichina confinis 

 growing a little distance above Pelvetia, and in some cases rising up into the 

 Ramalina belt. On the east coast Lichina confinis and L. pygmaea form two 

 narrow bands above and below the Verrucaria maura belt respectively ; in 

 the few places examined L. pygmaea was most often seen about 4 feet below 

 high-water mark of spring-tides. 



From the above account it will be seen that L. confinis and L. pygmaea 



