Dr Lauder Lindsay on the Flora of Iceland. 87 
the time no proper means of preserving them; and though I 
subsequently submitted them for determination of the species 
to one of our most eminent algologists, no communication 
haying been received from him, I infer that the specimens 
were in such a condition as to render their determination 
impossible. 
I found Poa annua and Stellaria media growing in 
hot mud on the margin of the springs, and with their roots 
in the hot water, their leaves immersed in steam. ‘The 
former was apparently healthy and vigorous; the latter was 
dwarfed and bleached, closely resembling Montia fontana, 
for which, indeed, it was at first mistaken. The ground im- 
mediately around the springs was unusually verdant, being 
covered with a fine sward, on which many of our commonest 
British weeds grew in remarkable beauty and luxuriance. 
Such were Plantago major, Potentilla Anserina, Prunella 
vulgaris, Cardamine pratensis, Alchemilla vulgaris, Thymus 
Serpyllum, Taraxacum Dens-leonis var. palustre, Ranun- 
culus acris and repens, Pinguicula vulgaris, and various 
forms of Stellaria media and Cerastium vulgatum. The five 
plants first mentioned were especially large and handsome. 
Above the hot springs there is a marshy pond, the water of 
which is cold, stagnant, and ochreous from ferruginous im- 
pregnation. Here luxuriated Menyanthes trifoliata and 
Eriophorum polystachyon in beautiful flower; many Carices, 
especially forms of the common C. cespitosa; many grasses, 
such as Catabrosa aquatica, Gilyceria fluitans, Poa annua ; 
several Potamogetons, as P. natans, P. perfoliatus, and P. 
crispus ; and several Hquisetums, as EL. palustre, HL. limosum, 
LE. arvense, and EH. hyemale. The same luxuriance of vege- 
tation which characterised the immediate vicinity of the hot 
springs and of the marsh above them, was also met with on 
the banks of the Laugar for several hundred feet of its sea- 
ward course. The causes of this profusion and richness of 
vegetation are easily found in the increased temperature of the 
soil and of the air immediately above it, as well as in the con- 
stant abundance of a warm moisture in the said air, in the 
form of the steam which never ceases to arise from the hot 
water. 
