Arctic Plants: Morphology and Synonymy 49 b 



Characteristic of the species of Oxytropis collected on the expedition is the 

 paespitoae growth with numerous leaves forming compact cushions, especially 

 in 0. nigrescens and 0. arctobia The primary root persists; it is quite long 

 and relatively thick, frequently supplemented by secondary roots of almost the 

 same length and thickness. Numerous aerial shoots with the very short inter- 

 nodes completely hidden by the crowded, withered leaf-sheaths, stipules, rises 

 from the crown of the root, and these shoots are terminated by rosettes of, leave 

 surrounding the central flowering stem overtopping the leaves, as in 0. foliolosa, 

 0. campestris and 0. Roaldi; or the peduncle of the inflorescenceJs so short that 

 only the flowers themselves are raised, and only slightly so, above the foliage, 

 as in 0. nigrescens and 0. arctobia. The habit of these two species is thus identical 

 with that of Trifolium nanum from the alpine region of the Rocky mountains. 

 A specimen of 0. nigrescens from Camden bay consists of a compact cushion 

 measuring 18 cm. in diameter; the largest of 0. arctobia measured 12 cm. in 

 diameter. Common to these two species of Oxytropis and the Trifolium men- 

 tioned above is the two-flowered inflorescence, while in the other species there 

 are several flowers forming a head or a short, more open raceme. 



Hedysarutn Mackenzii Rich, shows the same habit as Oxytropis campestris, 

 but the flowering stems are much taller and branched, specimens from Ber- 

 nard harbour measuring 28 cm. in height; the inflorescence is racemose. 



Characteristic of these arctic Papilionaceae is thus the persisting primary 

 root; in most of these the growth is caespitose owing to the profuse development 

 of aerial shoots of which the basal internodes persist and from the leaves of 

 which new shoots arise, bearing leaves and flowers, and dying down to the 

 ground at the end of the season, leaving only the. lowermost part to persist 

 and repeat the ramification in the manner of a pseudo-rhizome. 



EMPETRACEAE. 

 Empetrutn nigrum L. 



Several specimens were collected on tundra, with flowers and fruit; the 

 branches showed the typical growth of the species and were quite long, reaching 

 30 cm. in length. 



ONAGRARIEAE. 



Epilobiutn latifoliutn L. 



The tallest flowering specimen is from Cape Barrow; it measures 20 cm. in 

 height, and several stems are developed from the woody, thick, primary root; 

 as to the size of the flowers, the dried petals measure 2.2 cm. in length and 

 about 1 cm. in width. The leaves are lanceolate, quite long, and relatively 

 narrow. In specimens from WoUaston land the flowering stems are much 

 shorter, only 9 cm. in length, and the leaves are short but very broad, oval in 

 outline. While thus the primary root persists and develops as a strong vertical 

 root, the basal subterranean stem-portions persist also and increase in thickness; 

 upon these buds become developed which give rise to the aerial, floral shoots; 

 thus we have in this plant a pseudo-rhizome with the primary root persisting and 

 increasing quite considerably in thickness. Among the numerous specimens 

 collected there was no indication of reproduction by means of root-shoots. 



E. angustifolium L. 



The Fire-weed is so widely distributed in the arctic regions that it is even 

 circumpolar, but it is nowhere as abundant in the polar regions as fa,_rther south, 

 throughout the entire northern hemisphere. And farther south it is especially 



24657—4 



