94 Scientific Proceedings, Royal Dublin Society. 



the lower surface slender hyphse similar to those described on page 90 

 penetrate and ranaify between the irregularities of the granite, thus anchoring 

 the upright growths to the rock surface. On the coarser and more weathered 

 quartzite rocks, where there is a suiSciently rougli surface and a fair supply 

 of moisture, a similar coalescence of the crustaceous attachments occurs, and the 

 Eamalina growths have a sward-like nature ; but on the smooth unweathered 

 qnartzites a sward of Ramalinas does not seem to be possible ; the basal 

 hyphse are unable to penetrate even the surface of the rock ; their hold is 

 therefore very slight and the plants are easily dislodged. 



The identification of these upper Ramalinas is a matter of some 

 difficulty. If the reaction test is relied upon, the majority of them would 

 fall under Ramalina euspidata, subspecies breviuscula. No. 73 of Leiglitou's 

 " Lichenes Britannici," from the top of Eoseberry Crags, and No. 47 of 

 Mudd's " Lichenes Britannicorum," which Crombie includes under this 

 subspecies, are identical with many of the Ramalinas from the upper growths. 

 Banuilina A. and some of the larger specimens of Ramalina B. resemble 

 var. crassa. The young growths of Ramalina A. and of Ramalina C. answer 

 exactly to Orombie's description of forma gracilescens of the same subspecies, 

 and might be referred to this were it not for the fact that many of their 

 fronds stained beautiful yellow and red colours when touched with tlie potash. 

 If the reaction test is disregarded, then the fact that the upper Ramalinas 

 are almost entirely barren would point to their being forms or varieties of 

 Ramalina scopiilorum growing beyond tlie natural habitat of this species. 

 Before leaving the Ramalina belt I would like to refer to some interesting 

 points mentioned by Sir J. D. Hooker in " Flora Antarctica " (7), about the 

 Ramalinas of Fuegia and the Falkland Islands, which I have only come across 

 since my account of the Howth Ramalinas was written. He states that seven 

 varieties of Ramalina scopiilorum are found in particular habitats along tlie 

 coasts of those countries. Of these only one variety produces fruit. This 

 variety, he says, is identical with the English Ramalina scopiilorum, and inhabits 

 rooks at a considerable elevation and at a distance from the sea, while the 

 barren forms are all found nearer the sea. This is the exact reverse of what 

 occurs along the Howth coasts. Sir Joseph Hooker, however, points out that 

 the conditions of climate in the situations wliere the fertile Ramalina grows 

 on the Falkland Islands, approach more nearly to those in which Ramalina 

 scopulorum grows in England than do the situations nearer the sea which 

 are moister in Fuegia and the Falkland Islands than they are in our own 

 country. 



Two other species are frequent, but not general, in the upper Ramalina 

 zone, viz. Ramalina Curnowii and R. subfarinacea. 



