268 THE JOURNAL OF BOTANY 



Antennaria dioica, Polygala serpyllacea, Hijpericum pulchrum, 

 Gentiana ca7npestris, Viola Biviniana in fruit (1 to 1^ in. high), 

 Euphrasia latifolia (1| in. high), Car ex pulicaris (near small 

 rocks), &c. As to abundance of plants in this area with regard to 

 the number of individuals, dwarf Linum catharticum certainly 

 held sway. Scattered over this area in very limited quantity — 

 where nothing else was growing — was a peculiar dwarfed variety 

 of Bubus saxatilis ; it had often but two dark green rugose leaves 

 on each shoot. One or two withered flowers were found after a 

 long search, and after a still further search, a very abbreviated 

 long shoot was found. Its habit and general character are worthy 

 of a varietal name. 



As it got bleaker higher up the slope at about an elevation of 

 from 180 to 200 ft., the turf became scarcer until the bareness was 

 about 80 per cent. The 20 per cent, area was occupied as follows 

 in a scattered formation : — Plantago maritima var. lanata (4), 

 Thymus Serpyllum (2), Statice Armeria (1), Agrostis tenuis (1) ; 

 the remaining 12 per cent, was taken up by Cerasthim arcticum 

 (nigrescent), ]4re7iftrm norvegica, Cerastium vulg'atum (a nigrescent 

 form), Arabia petrcea (with rosy petals), Festuca ovina (viviparous), 

 Carex Goodenoioii (with nigrescent perigynia), Silene acaulis, 

 S. maritima, dwarfed plants of the following — Linum catharticum, 

 Bhinanthus, Scilla verna, Antennaria dioica, Euphrasia latifolia 

 (white-flowered), Sagina nodosa, S. procitmbens, tiny bits of 

 Calluna, and in slight depressions Erica Tetralix, Habenaria 

 viridis, with three leaves spread out rosette-like on the soil, 

 Anthyllis Vulneraria, and Bumex Acetosa. Hygrophorus coccineus 

 was present in one place. Where the rocks had not weathered so 

 fast, little bosses stood out, and on and about these were Aira 

 prcecox, Cerastium tetrandrimi, often not more than 1 in. high, 

 with well-developed congested cymes in full fruit, and very dwarfed 

 Draba incana. 



Still nearer the low hill-top (the highest point was under 

 290 ft.), the turf became scarcer still, and there was quite 90 per 

 cent, of bareness ; the following plants still struggled to hold the 

 ground : — Agrostis vulgaris, Carex (barren), Plantago maritima 

 var. lanata, Scilla verna, Selaginella, Thymus Serpyllum, Viola 

 Biviniana, Prunella vulgaris, Antennaria dioica, Linum catharti- 

 cum, Potentilla sylvestris, Scabiosa succisa, Festuca ovina (vivi- 

 parous), and just a trace of Calluna and Lotus corniculatiis. The 

 Viola was often attacked by Puccinia Viola Schumann, and the 

 Euphrasia by Coleosporum Euphrasicd Schumann. 



This Serpentine yields chromic iron, and it is possible that in 

 some parts of the area there may be some harmful constituents of 

 the weathered rock which inhibit the growth of many plants, and 

 also hinder the ground from being fully occupied by those that 

 attempt to cover it, and if this be so, it may also serve as an ally 

 to the bleakness of the place in augmenting the dwarfing of the 

 plants. 



The nigrescence noticed in some of these plants of cold regions 

 is probably due to the survival of those which may have adopted 



