Primulaceae. 195 



1905, p. 214. Sylvén, 1905, p. 126. Blytt, 1906, p. 566. Osten- 

 feld, 1910, p. 61 (var. Gormannii). 



Plants preserved in alcohol from Öland (E. Warming si /s 1907). 

 Herbarium material from Arctic Siberia (the mouth of the Lena River, 

 1883; Dr. Bunge), and Arctic America (King Point, A. H. Lindström, 

 June 17th and 28th, 1906). The plants from the latter habitat be- 

 longed to A. Gormannii Greene, formerly considered a separate spe- 

 cies, but the only difference from A. sept, is the shorter pedicels; 

 Osten Feld therefore ranks it with the latter species, but as a special 

 variety (.4. septentrionalis var. Gormannii (Greene) Ostf.). 



A rosette plant of the Draba venia type (Brundin, Sylvén), 

 generally appearing as a hapaxanthic winter annual, but 

 sometimes it succeeds in attaining to pollacanthic growth 

 (Sylvén, one specimen from Uppsala). 



According to these authors, the seeds germinate at once 

 during the summer, and a great number of leaves are developed 

 before winter sets in. These remain green throughout the 

 winter, except the lowest in the rosette, hence they can re- 

 sume their assimilative functions in spring, as soon as con- 

 ditions permit. No special bud-scales are provided for pro- 

 tecting the growing-point and the embryonic leaf-tissues 

 against desiccation during the winter. The peculiar flat 

 form of the rosettes is caused by the upper leaves growing 

 more on the upper than on the lower surface, so that they 

 are deflected downwards, pressing the lower and older leaves 

 closely towards the substratum (Brundin). During the winter 

 the leaves assume a deep red-brown colour (ibid.). 



The primary root developes into a thin, slightly branched 

 tap-root; adventitious roots do not occur. 



The growth of the shoot terminates with a 7 — 10 flow- 

 ered peduncle; weak specimens develop only one peduncle, 

 whereas stronger ones produce several, through development 

 of the axillary buds of the upper foliage-leaves; on a spe- 

 cimen from Boganida, I have found 19 peduncles, and A. 

 septentrionalis is also depicted with several peduncles both 



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