296 THORODDSEN 



have 237 species in common. Of the higher plants in Iceland the 

 majority of the species belong to the Cyperacese (44) and the 

 Graminese (40), and these two families are also most characteristic 

 of the inhabited land and of the greatest importance as regards the 

 sustenance of the inhabitants. Of Composite there are 25 species, 

 of Caryophyllacese 24, Cruciferse 22, Juncacese 17, Filices 17, Rosacese 

 16, Scrophulariacese 13, Papilionaceas 12, etc. 1 The lower plants have 

 not yet been closely investigated; there are known, however, 300 

 species of mosses, 233 species of lichens and 543 species of fungi, 

 452 of which are parasites; on Betula odorata have been found 54 

 species of parasites, on Salix lanata 14 species, on Dry as octopetala 

 11, and on Betula nana and Salix glauca 10, etc. The mushrooms, 

 of which manv occur, are as vet but slightly known. - 



/ / / 



Naturally, nothing is known as to how many species have 

 immigrated into Iceland since the first colonization of the island in 

 874, but we may take for granted that the number is considerable. 

 Even by the first "Landnamsmen" several species were undoubtedly 

 imported from Norway and perhaps also from the islands along 

 Scotland. In the Sagas we read about live-stock (cows, horses, sheep 

 and swine) being brought to Iceland and in the fodder brought 

 along with them there were certainly several foreign seeds. Some 

 of the immigrants for religious reasons, brought earth with them 

 from Norway from the site of their former temple (Hof). Then the 

 settlers also used foreign seed for cereal crops, on the cultivation 

 of which they were very keen at first. Moreover, different species 

 may have been introduced along with articles of commerce and in 

 other ways. Of imported species, which during later centuries have 

 gained a firm footing and have become naturalized, the most com- 

 mon are Urtica urens, U. dioeca, Cirsium arvense, Spergula arvensis, 

 Carnm carui, Lamium intermedium, Seuecio vulgaris and some others. 



1 Eug. Warming: Tabellarisk Oversigt over Gronlands, Islands og Fa?roernes 

 Flora, 1887. (Vidensk. Meddel. fra den naturhist. Foren., 1887. Kobenhavn, 1888). 



1 Chr. Gronlund: Islandske Naturforhold med saerligt Hensyn til Mosvsextens 

 Betydning for Landskabet (Tidsskrift for populaere Fremstillinger af Naturviden- 

 skaben, 5. Rsekke, IV, 1877, pp. 321 356). Bidrag til Oplysning om Islands Flora, 

 Lichenes, Hepaticse og Musci (Bot. Tidsskr., IV, 1870, pp. 147172; 2. Rsekke, III, 

 1873, pp. 1 26). Afsluttende Bidrag til Oplysning om Islands Flora, Musci, Hepa- 

 ticse, Lichenes (Bot. Tidsskr., XIV, 188."). pp. 159217). Tilla?g til Islands Krypto- 

 gamflora, indeholdende Lichenes, Hepaticae og Musci (Bot. Tidsskr., XX, 1895, pp. 

 90115). Islandske Svampe samlede 1876 af Chr. Gronlund ^Bot. Tidsskr., XI, 

 187980, pp. 7276). E. Bostrup: Islands Svampe (Bot. Tidsskr., XIV, 1885, pp. 

 218229; XXV, 1903, pp. 281335). 



