84 



herbacea, at an altitude of 2,900 feet. Ordinary A. flcxuosa occurs on the Tarens 

 of the Black Mountain ; the var. montana is apparently absent from them. 



38. Poa alpina, L. 1. Northern Group. Clogwyn-y-Garnedd and 

 Cwm Glas Bach, Snowdon, at about 2,800 feet, in small quantity. This Alpine 

 grass, which occurs pretty abundantly on the Helvellyn Cliffs in Lakeland, and is 

 abundant throughout the Scottish Hii,'hlands, occurs in small quantities, and 

 in a small form, in the above stations in Carnarvonshire. Absent from the 

 Carnedd Dafydd Cliffs ? ; absent southwards. It is, throughout Great Britain, a 

 strictly precipice plant. 



39. Poa glauca, Sm.. 1. Clogwyn-y-Gamedd, Snowdon, on the 

 authority of specimens gathered by Mr. W. Wilson. I do not feel sure that I 

 distinguish this Grass correctly from the forms next mentioned ; but I believe that 

 I have met with it this year in Clogwyn-y-Garnedd, at about 2,800 feet. A Grass 

 picked by me at Carnedd Dafydd in 1876 was doubtfully referred to this by Prof. 

 Babington ; but belongs, I think, rather to the next. Northern Group : not found 

 southwards, nor in Lakeland ; very rare in the Highlands of Scotland. 



40. Poa Balfourii, Bab. 1, 2, 3. Northern Group. I refer to this 

 plant, a distinctly glaucous grass, gi-owing mostly with single stems, or at the 

 most tufted, not csespitose, which occurs upon most if not all the cliffs of Carnar- 

 vonshire. I have not seen this form upon the cliffs of the Central or Southern 

 Welsh Groups ; but it occurs on the Helvellyn Range in Lakeland and in the 

 Scottish Highlands. 



41. Poa Balfourii, Bab., var. montana? 3, G, 7. Northern and 

 Southern Groups. Under this name I intend another member of this troublesome 

 group, which certainly appears to me to stand well apart from the last mentioned. 

 It is a larger, densely CEespitose grass, without any approach to the glaucous 

 bloom noticeable on P. Balfourii. This is very abundant in the Carnedd Dafydd 

 Cliff, and probably in other Carnarvonshire stations ; and the same, or a closely 

 allied form, recurs abundantly upon the central cliff of the Brecon Beacons and in 

 the Black Mountain, at Taren-r'-Esgob, in Breconshire ; and at the Red Daren, 

 and on that of the Olchon, in Herefordshire proper. 



42. Hymenophyllum unilaterale, Willd. 1, 2, 3, 4, 5, G, 7. 

 Northern, Central, and Southern Groups. Widely distributed as this Pilmy 

 Fern is upon mountains, it reaches, perhaps, a greater abundance upon the 

 precipices of higher mountains than in any other position. It seems to be in such 

 positions well-nigh universally present. It is abundant in the Brecon Beacon 

 Range, and just touches that of the Black Mountain at Taren-r'-Esgob ; but has 

 never been found within the bounds of the Herefordshire Flora. 



43. Asplenium viride, Huds. 1, 2, 3, 4, 5, 6, 7. Northern, Central, 

 and Southern Groups. This fern, like the last, is rarely absent from any 

 mountain precipice ; but it often occurs in very small quantities, probably owing 

 to the depredations of collectors. I have myself found it upon every one of the 

 cliffs enumerated in this paper; and it is a well-known inhabitant of Taren-r'- 

 Esgob in the Black Mountain Group, to which spot, however, it is by no means 

 confined in this group of hills. 



