McArdle — Additions to the Hepaticce of the Mill of Hoioth. 113 



year, during wliich time I paid it several visits ^yith good results, and 

 the list would not be so extensive if this request had not been granted. 

 Such species as the rare Jungermania minuta, Scapania (Bquiloba, 

 and Lejeimea flava var., grow in great luxuriance. The last, in 

 company with the commoner species Lejeunea serpyllifoUa^ clothes the 

 large stones, and the stems of trees which margin a small stream. 

 The pretty Lejiidozia reptans and L. cupressina grow in large cushion- 

 like patches, and such exuberant growth I have only found at 

 Killarney. The centre of the demesne is sheltered on all sides, 

 ancient lianas of honeysuckle hang from tree to tree, and on these 

 and the fallen and decaying logs, with the damp genial atmosphere, 

 liverworts and mosses grow in profusion. I do not know a prettier 

 sight than the banks of Pellia epiphylla, and Lophocolea lidentata, 

 yards in extent, with their white pellucid fruit stalks glistening 

 with dew-drops, rising from the green velvet carpet of fronds, which 

 I enjoyed in the wood one April day. The outer portion is backed 

 up with stately conifers and rare shrubs, which quite surround the 

 historic castle. The termination of the demesne at the hill is a natural 

 rockwork, planted with choice rhododendrons, which grow luxuriantly, 

 some of them attaining large dimensions, and, when bearing their 

 trusses of bloom, are a sight well worth going there to see. 



To my former list I have added nineteen species. One of these is 

 new to the Irish Elora, and foui'teen are additions to the Co. Dublin 

 list of Hepaticse ; also seven varieties of more or less botanical 

 interest. The total number of species now known to grow on the 

 "FTin of Howth is fifty-five. The appended Table, which shows their 

 geographical distribution, will, I trust, be interesting, and I have 

 endeavoured to make it as complete as possible, so far as the material 

 for doing so at my disposal would allow. A glance over it will show 

 that some of the Howth plants are local in Ireland. At the present 

 time Howth is the only locality recorded in Ireland for Ceplialo%ia 

 Francisci, and Jungermania attenuata. Plagiochila asplem'oides is rarely 

 found in fruiting condition, so I have given a description of the male 

 plant, which does not seem to be well known. The range of most of 

 the species in Scandinavia and the Pyrenees is very striking, and it 

 is interesting to note that the Hill of Howth plants extend mostly 

 over the northern continent of Europe to North America, and from 

 Pikes Peak, across the Rocky Mountains, to Cape Horn, Australia, 

 New Zealand, Cape of Good Hope, West Indies, and Java. Pour ai'e 

 found on the Island of Tenerilfe, others in the Azores and Canary 

 Islands. All the species, excepting three, are also found in Yorkshire 



K.I.A.PKOC, SEE. in., VOL. IV. I 



