390 MiT Watson's Observations on the Temperature 



spring wells near the top of Ben-Nevis (alt. 3758 feet, on the 

 west side) was 39°; a bubbling spring, forming a small well at the 

 height of 2209 feet on the moors northward of Loch Eil, Ar- 

 gyleshire, gave 43° ; both, probably, influenced by the atmos- 

 pheric temperature. 



After passing 2000 feet in the eastern Highlands. 1500 feet 

 in the western, and 1000 feet in the north-western, vegetation 

 undergoes a decided and rapidly increasing deterioration. Cul- 

 tivation has ceased ; trees dwindle down to meagre bushes, and 

 the graceful verdure of our fields and groves gives place to a 

 small rigid vegetation, such as clothes the shores of Arctic lands. 

 The following is a list of species which I have observed between 

 the heights denoted. Several of them iiiay occur (especially on 

 the Breadalbane mountains) rather higher than is here specified. 

 All I can yet say is, that they do grow at least as high or as 

 low, and probably not much more ; but, no doubt, some of the 

 spring flowers below 2000 feet were overlooked. 



Species above 4000 feet. — Aira alpina, Carex rigida, Empetrum nigrum 

 (very rarely), Festuca verna, Gnaphalium supinum, Juncus trifidus, Leon- 

 todon palustre, Luzula arcuata, L. spicata, Oxyria reniformis, llumex Ace- 

 tosa, Salix herbacea, Saxifraga stellaris, Sibbaldia procumbens, Silena acaulis, 

 Vaccinium Myrtillus, Viola palustris. The absence of soil, rather than the 

 height, probably arresting others. To these 17, we may add 6 others seen 

 on the very summit of Ben-Lawers, which is said to be 4015 feet above the 

 sea ; viz. Cherleria sedoides, Cerastium alpinum, Polygonum viviparum, 

 Saxifraga oppositifolia, S. nivalis, Saussurea alpina. Total 23. 



Species between 3000 and 4000 feet. — Achillaea Millefolium, Aira flexuosa, 

 Alchemilla alpina, A. vulgaris, Anthoxanthum odoratum, Apargia Taraxaci, 

 Arabis petraea, Arenaria rubella, Azalea procumbens, Calluna vulgaris (rare, 

 and never to 3500 feet), Caltha palustris. Campanula rotundifolia, Cardamine 

 hirsuta, C. pratensis, Carex dioica, C panicea, C^ pilulifera, C. pulea, Ceras- 

 tium latifolium, C. viscosum, Chrysosplenium alternifolium, C. oppositifo- 

 lium, Cochlearia officinalis, Draba rupestris, Eleocharis caespitosa, Epilobium 

 alpinum, Eriophorum angustifolium, Euphrasia officinalis, Galium saxatile, 

 Juncus biglumis, J. triglumis, Myosotis alpestris, Nardus stricta, Narthe- 

 cium ossrfragura, Oxalis AcetoseUa, Poa alpina, P. annua, Ranunculus acris, 

 Rhodiola rosea, Rubus Chamsemorus, Salix reticulata, Saxifraga cernua, S. 

 hypnoides, S. rivularis, Silene maritima, Statice Armeria, SteUaria cerastoi- 

 des, S. uliginosa, Thalictrum alpinum, Thymus serpyllum, Tormentilla offi- 

 cinalis, Trifolium repens, Tussilago Farfara, Vaccinium uliginosum, V. 

 Vitis-Idaea, Veronica alpina, V. serpyllifolia. In all 57 species. To these 

 may be added the 23 former, all of which (except Luzula arcuata) I have 

 seen below 4000 feet. Ia. arcuata, in Sutherland, must be below this, if not 

 below 3000 feet. Total, 80 species. 



