90 Scientific Proceedings, Royal Dublin Society. 



was more pronounced in the plants growing further from the open sea or on 

 rocks where they were protected from the salt water. 



Ramalina scopulorum is not so abundant on the east and north coasts. 

 Easterly winds are dry and infrequent, consequently there is not so much 

 moisture or spray on this part of the peninsula. The plants are small, 

 with slender bristles which are sometimes thickly covered towards the 

 ends with young apothecia and spermogoiies or galls, and resemble the form 

 described as growing on dry sheltered I'ocks on the south and south-west 

 coasts. 



The lower Eamalinas grow in tufts from a corticated cusliion-like base 

 which is often of considerable area, and in old-established tufts may be more 

 than J inch in thickness at the centre. From the lower surface numerous 

 slender branching hyphse penetrate in rhizoid-like strands between the 

 irregularities of the rock, and wind themselves round the small projections, 

 sometimes enclosing particles of the rock in their meshes. As the tissues of 

 the fronds are continuous with those of the basal area, they are thus securely 

 anchored to the substratum. The Ramalina tufts are always more numerous 

 on rocks witli rough surfaces. When they grow on smoother rocks, they are 

 more frequent on those that are already covered with crustaceous species. 

 Fresh growths seem usually to spring from the periphery of the attachment 

 area, and young fronds are often to be seen springing up in considerable 

 numbers to replace tliose that have been broken ofi by the wind and 

 waves. In this way tlie Ramalina tufts may renew their growths almost 

 indefinitely. It is quite common to see almost all the old growth shorn off 

 at one side of the basal cushion and a crop of stiff young fronds springing 

 up from another part. 



Besides the young growths which arise from the basal cushions, the 

 beginnings of new colonies — probably sporelings — were frequently met 

 with. On one small piece of rock chipped off a flat boulder on the 

 shore at Stella Maris, the surface of which was completely disguised by a 

 covering of Buellias, 27 small colonies were counted on an area of about 

 2 square inches, and a great part of the boulder was dotted in the same way. 

 The colonies were all in early stages of development, many of them were 

 entirely crustaceous and not much larger than a pin-head, but others had 

 already put forth small tufts of slender upright fronds. On a higher rock 

 above this flat boulder were many fine colonies of mature fertile plants of 

 RamaUna scopulorum. 



The Upper Ramalina Zone. — The Ramalinas of the upper zone are much 

 more abundant and seem to vary more in appearance than those of the 

 Ramalina ncopulorum zone. Three well-marked forms occur, which in places 



