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*Ulex Europæus, and *Crategus oxy- / *Endymion nutans. A garden plant a
acantha. Well known to have been Balta Sound and Springfield, Unst. planted at Tingwall.
(Sparganium ramosum. O.; S. simplex.) *Vicia sativa. Cultivated at Tingwall. O. Potamogeton lanceolatus, probably a *Sedum Fabaria. (P = S. Telephium.' state of P. heterophyllus.
Edmonston.) Gardens, Haroldswick, *Phleum pratense. “Probably introUnst, etc.
duced.” 0., F. (Serrafalcus mollis, *Carum Carui. Probably planted ori. Alopecurus pratensis, and even Dac
ginally, but now apparently wild. I tylis excite a suspicion in my mind Anthemis Cotula. Tingwall, a very as to their being truly indigenous ; suspicious locality.
I have not seen them in natural Petasites vulgaris. Tussilago Farfara pastures, but only in prepared grass
occurs in the station given by Ed-| lands.) monston for this species ; I suspect Poa compressa. An error ? some accidental error has crept in Cynosurus echinatus. Introduced or here.
erroneously determined. Mentha viridis. “Likely not indige- Serrafalcus commutatus. Introduced ? nous,” Edmonst.
Lolium temulentum. ?=L. italicum. Plantago media. Introduced as in the Introduced. Orkneys and Feroes.
* Avena sativa. Wayside, Balta, Unst. Lastrea Thelypteris. An error ?
III. GENERAL BOTANICAL FEATURES. The facies of the flora of the Shetlands is very striking ; especially are the land slopes bordering the sea singularly rich in plants more abundant in petals than leaves. This profusion of blossoms is in keeping with the operation of a law, that in proportion as the babitat proves ungenial (threatening the life of the individual, dwarfing the stem), so the flowers increase in number and proportionately in size; and thus the whole plant becomes more fruitful in behalf of its kind.
But a few plants only are found differing in this respect; most markedly among such is Bunium flexuosum, which attains a height of from 21 to 3 feet. In many sheltered situations among the sea cliffs the vegetation is very luxuriant, and presents no essential differences from a like vegetation in the south of England.
This tendency to produce an excessive development of floral organs very generally gives rise to abnormality. Viviparous states of Festuca ovina and Lolium perenne are very common; polypetalous flowers with petaloid stamens have occurred to me in Erica Tetralix, the stem-leaves of Cardamine pratensis transformed into flowering racemes ; the uppermost bract of Caltha palustris petaloid ; in Mr. C. W. Peach's collection is Leontodon Turaxacum, its scape bearing a
leaf at the distance of one-eighth of its length from the apex; and many others of the like nature were noticed by me.
The maritime vegetation presents few characteristics. The dominant species of the natural pastures are— Festuca, Anthoxanthum, Lotus, Scilla, Thymus, Polygala, Ranunculus repens, Rhinanthus, Bellis, Prunella, Galium saxatile, with Orchis maculata, Habenaria viridis; the marshes dispersed among the pastures have for their characteristics, Myosotis repens, M. cæspitosa, Menyanthes, Pedicularis palustris, Stellaria uliginosa, Iris, Juncacea, and Carices.
The common agrestal plants are, Viola tricolor, Spergula, Cerastiums, Lamium purpureum, Galeopsis Tetrahit, Lycopsis, Veronica agrestis, V. hederifolia, and Myosotis.
Papaver dubium, Viola arvensis, Geranium molie, Valerianella, Fumaria officinalis, and Lamium intermedium are confined to sandy soil.
The plants of the moorlands and bogs are such as are usually met with throughout Great Britain.
Though it is possible, when the distribution of plants in these isles is viewed as a whole, to distinguish vertical zones of vegetation, yet a very large number of the species, elsewhere well defined in their range relatively to others, in the Shetlands encroach and modify the vegetation of a lower or higher zone, as almost to set aside any attempt to utilize, at least for a limited district, the vertical range of the species. Thus, a few alpine plants may be here recognized as occurring at much lower levels than elsewhere in Britain :
Thalictrum alpinum, 1-1460 feet; Arabis petræa, 70 feet; Draba incana, 70-460 feet; Gnaphalium Norvegicum, 100 feet; Polygonum viviparum, 0-1476 feet ; Salix herbacea, 900–1470 feet ; Empetrum nigrum, 0–1000 feet ; Saussurea alpina, 800-1400 feet; Carex rigida, 800-1400 feet.
However, the general vertical distribution of the plants seems to be as follows:
1. The Superagrarian Zone of vegetation, here extending from the sea-shore up to an average elevation of about 100 feet.
2. The Infer- and Mid-Arctic Land Zones, not clearly separable ; the Infer-Arctic extending to at least 600 feet. These zones embrace the remaining surface, excepting the summit of Ronas Hill, which is characterized by a Super-Arctic vegetation.
3. The Super-Arctic Zone commences at an elevation of about 800
feet on Roxas Hill, and its flora is represented by Azalea procumbens, Carex rigida, Saussurea alpina, Alchemilla alpina, Salix herbacea, Sibbaldia procumbens.
As regards the geological distribution of the plants little can be said, for though the lithological characters of the rocks are so varied, and though the rocks appear at the surface, and thus present conditions favourable for the modification of the flora, yet little influence is exerted upon the vegetation. That of the Serpentine and Euphotide rocks presents some prominent features ; peat, which is generally so abundant on the gneiss, mica, slate, granite, and sandstone, is almost absent on the Serpentine and Euphotide ; Arabis petræa, Draba incana, Arenaria Norvegica, Cerastium latifolium, Anthyllis vulnerarin are restricted to them.
The granite of Ronas Hill yields many peculiar plants, but they owe their presence to the superior altitude (1476 feet) of the hill on which they occur as subalpine forms of vegetation, and cannot be regarded as truly granite-loving species.
The plants restricted to a sandy soil have been already given.
IV. COMPARISON OF THE FLORA OF SHETLAND WITH THAT OF
THE ORKNEYS AND THE FEROES. The Shetland Islands occupy a geographical position intermediate between the Orkneys and the Feroes, and strikingly contrast with them as regards geological structure. Thus the dominant rocks of the median archipelago belong to the metamorphic series and the Old Red Sandstone formation, the former being represented by serpentine, mica slate, gneiss, and granite; the latter by grits and sandstone. Little or no drift-matter encumbers the solid rocks. Whilst, on the one hand. the rock-formation of the Feroes is basalt, said to be comparatively poor in species, on the other, the rocks of the Orkneys all belonging to the sedimentary series, are sandstones, grits, and argillaceous sandstones. It is therefore a very interesting subject of inquiry, as to the botanical relation existing between these three groups of islands.
No very marked differences in climate exist between the Feroes. Shetlands, and Orkneys; the mean annual temperature of the most northern group of islands is 45°-16, being very little below that of the Orkneys, which is 46°.204, whilst it exceeds that of the Shetlands by 0°.434. Though there is such a similarity in climate between the