FLORA OF CANADA. 3 



Canadian plants being also common in Lapland and arctic Russia. A 

 number of species occurring chiefly in the most western parts of arctic 

 Canada are of Asiatic relationship, and very few are of American 

 origin. Among these may be mentioned Douglasia arctica, Cardamine 

 digitala, and Pleuropogon Sabini. 



With regard to general characteristics, the arctic flora of Canada is 

 quite similar to the arctic or "circumpolar" flora in general. It is 

 composed almost exclusively of perennial plants, which exhibit those 

 well known features with regard to biology and anatomical structure 

 which the arctic flora has in common with the flora of high alpine regions. 

 In the more northern parts, where the ground is physiologically more or 

 less dry, or where it is rocky, the growth is often very compact and 

 includes a great number of plants of the so-called "bunch type." 

 Suffice it to mention Silene acaulis, Papaver radicatum, Potentilla nivea, 

 Saxifraga tricuspidata, S. oppositifolia, Armeria sibirica, Androsace 

 Chamcejasme, Melandrium apetalum, Kobresia Bellardii, Car ex rupestris, 

 C. membranopacta, C. nardina, Poa glauca, Festuca ovina var. brevifolia, 

 etc. Similar growth is also encountered, though less commonly, on the 

 tundra, i.e., the more southerly and physiologically wetter part of the 

 arctic region. Among the tundra plants of the bunch type may be 

 mentioned: Diapensia lapponica, Arenaria macrocarpa, A. arctica. 

 Compactness of growth is also displayed by a number of plants which, 

 though not growing in "bunches" form dense and often very extensive 

 mats. To this type belong Cerastium alpinum, Ranunculus hyperboreus, 

 Sibbaldia procumbens, Dryas integrifolia, Loiseleuria procumbens, Cassiope 

 tetragona, etc. Among the more conspicuous arctic herbaceous plants 

 which grow neither in mats nor in bunches may be mentioned : Dupontia 

 Fischeri, Eriophorum Scheuchzeri, E. angustifolium, Spiranthes Roman- 

 zoffiana, Habenaria hyperborea, Oxyria digyna, Polygonum viviparum, 

 Ranunculus nivalis, R. affinis, Parrya arctica, Eutrema Edivardsii, 

 Saxifraga flagellaris, S. hieracifolia, Pyrola grandiflora, Primula sibirica, 

 Pedicularis flammea, Arnica alpina, Saussurea alpina, Chrysanthemum 

 integrifolium. 



As indicated above, the Arctic zone has no real trees. The woody 

 plants, characteristic to the zone in general, are either prostrate forms, 

 such as Salix arctica and its varieties, S. orbicularis, S. anglorum, or of a 

 more shrubby appearance, such as Betula nana, B. glandulosa, and Salix 

 Richarsonii. On the tundra, the woody plants are chiefly of the erica- 

 ceous family, the principal ones being Ledum palustre, Rhododendron 

 lapponicum, Vaccinium uliginosum, V. Oxycoccus, V. Vitis-Idcea var. 

 pumilum, Arctostaphylos alpina. The berries of the two latter species, 

 with those of Empetrum nigrum, form the chief food of the migrating 

 geese in the spring of the year. 



