304 THE STORY OF PLANT LIFE 



Natives of dry climates, they exhibit adaptations 

 for resisting drought, and are largely xerophytic. The 

 Agaves, for instance, have thick fleshy leaves with a 

 waxy covering. A large number have a bulbous 

 rootstock, and in this case produce leaves only in the 

 wet seasons. In other cases the stem is leafy. The 

 leaves, which are radical, are parallel-veined and as 

 a rule narrow. 



The inflorescence is cymose or may, in form, be 

 like an umbel or a spike. There is a naked 

 scape and a spathe. The flowers are regular, or 

 irregular, hermaphrodite. They bear bracts. The 

 perianth is superior, petaloid, and made up of six 

 segments, in two whorls, and the mouth of the tube 

 may be formed into a corona, as in Narcissus, which 

 is regarded as the combined ligular outgrowths of 

 the perianth leaves, or as the stipules of the stamens. 

 There are six stamens, which are rarely epigynous 

 and seated on the perianth-tube or base of the 

 segments. The anther-stalks are free or united at 

 the base. The anthers are linear, oblong, turned 

 inwards, versatile, opening inwards or by terminal 

 pores. The ovary is inferior, or adherent to the 

 perianth-tube, ovoid or rounded, three-celled, con- 

 sisting of three carpels, with axile placentae. The 

 style is slender or columnar. The stigmas are one 

 or three. The ovules are numerous, anatropous, in 

 two series, in the inner angles of the cells. The 

 fruit is usually a capsule, sometimes a berry, and 

 fleshy, three-celled, three-valved, opening by loculi. 



