38 B Canadian Arctic Expedition, 1913-18 



Parrya macrocarpa R. Br. [Matthiola nudicaulis (L.) Trautv., Parrya nudi- 



caulis (L.) Regel.] 



Several flowering and fruiting specimens were collected; during the flowering 

 the height of the stem, averages about 10 cm. The primary root is deep, and 

 very thick, bearing at the crown some few short erect or ascending shoots, 

 densely covered with remnants of old leaves, and terminated by a fascicle of 

 leaves surrounding the flowering stem. With regard to the vegetative repro- 

 duction, it would appear as if the species is very poorly equipped, since there 

 is no other subterranean stem than the very short pseudo-rhizome, described 

 above. However, the root-system shows that the plant is by no means unable 

 to wander and thus become distributed in a vegetative manner since the large 

 tap-root frequently branches and some of these branches, especially the hori- 

 zontal ones, are able to produce new plants as root-shoots. 



For instance, some flowering specimens collected on Herschel island and 

 Wollaston land were actually root-shoots, with the mother-root still attached. ■ 

 Similar root-shoots occur in a number of plants; Wittrock ^ has written an 

 interesting paper on this subject furnishing a comprehensive list of species that 

 multiply in this manner. Among the Cruciferae Wittrock mentions some species 

 of Arabis, Cardamine resedifolia, Lepidium latifolium, Alliaria, and several 

 Nasturtia. 



P. arctica R. Br. 



A relatively smaller plant than P. macrocarpa but the root is also here quite 

 thick and deep. The aerial shoot, inflorescence, and leaves, agree with that of 

 the preceding, but I found no specimens developed from roots. 



Erysimum inconspicuum (Wats.) MacMill. [E. parviflorum Nutt., non 

 Pers.] 



The tall flowering stem (about 24 cm.) arises from a small rosette of leaves 

 borne upon a slender but persisting primary root which ramifies freely; the 

 species is perennial. 



Sisymbrium sophioides Fisch. 



On Herschel island this species may persist for more than one season, as 

 shown by a very large specimen with six flower-bearing stems reaching the 

 height of about 30 cm. and arising from a large rosette of leaves; the thick 

 primary root bears evidence of having been active for at least two seasons. 

 The specimen was collected in the month of August and with it several much 

 smaller specimens were collected. Averaging only 3 to 5 cm. in height, these 

 plants were in bloom, and the rosette of leaves was perfectly fresh; thus they 

 might be able to winter over. It deserves attention that this species is generally 

 described as an annual and that it occurs as such in arctic Scandinavia (70° N.L.) 

 according to Blytt;^ it has also been found near Ivigtut, on the west coast of 

 Greenland, but as an introduced weed only. 



CRASSULACEAE. 

 Sedum Rhodiola DC. 



The very carefully lifted specimens form relatively large compact cushions 

 with the numerous low, flower-bearing stems, about 5 cm. in height, borne upon 

 fleshy subterranean branches with numerous withered stems from previous 

 years, and terminating in a deep, relatively slender, primary root. As com- 

 pared with Greenland specimens, those from Martin point, Alaska, are much 

 less robust with respect to the size of leaves and inflorescence. 



I Botan. Notis. Lund, 1884. 



1 Norges Flora, p. 995. Christiania, 1861. 



