176 



The year -shoots have small, scattered, scaly leaves, mere 

 rudiments which can play no part in assimilation. In their 

 axils lateral shoots occur which are smaller than the main shoot 

 and bear scale-leaves. The year-shoots are therefore bran- 

 ched. The lateral shoots (year-shoot branches) bear flowers 



in the upper leaf-axils. 



Before the beginning of 

 the next vegetative period, the 

 ultimate parts of the year- 

 shoot and all its smaller bran- 

 ches die, and only the pri- 

 mary axis (the main shoot in 

 fig. 24) remains, after losing 

 its green bark and assuming 

 the yellow, smooth, hard bark 

 instead. The branches of the 

 year - shoot thus live only 

 through one vegetative period, 

 they are biologically equi- 

 valent to leaves and may be 

 termed assimilation-branches. 

 (RINDOWSKY, see below p. 178). 

 The next year-shoot arises 

 from the nodes of the primary 

 year-shoot where the assimil- 

 ation-branches formerly were 

 or where their remains may 

 still be seen, so that serially 

 the new shoots arise below 

 the old ones. During the first 

 year, between the assimilation- 



Fig. 24. A year-old branch of Eremo- 

 sparton aphyllum. A bunch of new 

 assimilation-shoots arising from an 

 old leaf-axil at the base of three dead 

 (strongly shaded) assimilation-shoots. 



branch and the scale-leaf sub- 

 tending it, one may find the 

 little bud which develops into a new year-shoot (fig. 25). 

 Sometimes not one but several shoots are formed from a 

 node, some of these being vigorous and persistent, while 

 others are short-lived assimilating shoots. It has not been 

 possible to determine whether these serial shoots are lateral 

 shoots on an assimilation-branch of the first year, or on 



