ALBERT AND GABRIELLE HOWAHD. 95 



Sub-class 'I. Leaves lanceolnte : ratio lengfth to l)readtli 

 between 3 and 4. The types contained in this sub-class form, as 

 regards habit : a series of which the two extremes are the dwai-f 

 form, type IX, with all its leaves forming a rosette on the ground, 

 and type XVII in which the leaves are arranged at regular 

 intervals up the stem, none being on the ground. This sub-class 

 can be conveniently divided into three sub-divisions accordino- to 

 the habit ; type XIII may be considered as a transition form 

 betweer sub-divisions {h) and (c). 



[a) Internodes short ; all the large leaves form a rosette on 

 the ground. 



Only one type (IX) belongs to this sub-division. It is readily 

 distinguished from the other types of this sub-class by the habit 

 and by the peculiar crinkling of the inflorescence leaves. 



