Rosaceæ. 



83 



exemplifies this; but the development is nevertheless of two 

 years duration. The plant has, however, a much greater 

 power of wandering, because it gives off horizontal runners 

 which may attain a length of above 30 cm. Fig. 32, A, B 

 are apices of the latter in the wandering and resting stages 

 respectively. These well-marked wandering shoots arise from 

 deeper-lying parts of the plants, and their two-rowed sheath- 



1912 



Fig. 32. Rubus chamæmorus. 



A, Apex of a runner (Norway; July 22); k, bud B, Runner with resting bud in which 

 the first foliage-leaf is formed (Denmark; Oct. 6). C and D are branch-systems in the 

 winter-stage (Denmark ; Oct. G). The shoots marked 1912 have that year been assimilatory 

 shoots, from their base new shoots arise bearing winter-buds. Portions of axes marked 

 1911 and 1910 have been assimilatory during these years. All the figures are about 



natural size. 



like scale-leaves may subtend new runners. In the begin- 

 ning of autumn they may either develop a resting bud which 

 is situated almost at the surface of the bog and which in 

 Denmark in October contains the first foliage-leaf of the 

 assimilatory shoot of the next year, or the runner may live 

 through the winter deeper down in the bog without devel- 

 oping a resting bud proper and next summer resume its 



6* 



