232 



not exceed a height of 30 centimetres. Sometimes it may 

 be a hemicryptophyte, but in its least protected form it is a 

 chamaephyte. with a low thick perennial epigeal base, which 

 bears rather short green branches. These bear opposite 

 subulate leaves with the axils woolly-haired, and with the 

 basal part persisting through the winter. 



I have not seen the plant in flower. The fruit is said 

 to be somewhat fleshy and wingless. 



As regards the assimilating, epidermal, and aqueous 

 tissues, the structure of the leaf and stem is similar, both 

 belonging to the centric type. A thin-walled hypoderm 

 contains crystal-groups. (Fig. 57). 



The Chamaephytes described have the following char- 

 acters in common: They are undershrubs with a perennial 

 lignified and often thickened base, and with year-shoots the 

 larger distal part of which dies before the next vegetative 

 period. Nanophytum alone is a cushion-plant, or nearly so. 



With the exception of Capparis, they have all small 

 leaves, and some of the Chenopodiaceae are practically leafless. 

 In some species all or some of the leaves are shed during 

 summer, and the stems assume the function of assimilating 

 organs (Alhagi, Convolvulus). 



The structure of the leaves is isolateral except in Fran- 

 kenia. The leaves of many species are coated with hairs, 

 some have tracheids, others aqueous tissue. 



The year-shoots are almost always branched which is 

 the rule for undershrubs (WARMING 1892). 



As already stated all the chamaephytes are late flowering. 

 The structure of the fruit so far as I have observed, presents 

 no general characteristic common to all. 



C. Hemicryptophytes. 



The majority of these (see chap. 12, p. 167) are spring- 

 plants the aerial parts of which are dead during the warmest 



