-ECT. II 



THANEROGAMIA 



705 



spent inflorescence together with a young bud bearing a number of leaves. Each 

 of these leaves is provided with an embryonic lamina, while the continuation of 

 tlie shoot is the embryonic inflorescence. In spring the leaves grow into long, 

 linear structures, and, together witli the inflorescence, appear above ground. The 

 inflorescence is sparingly branched ; the white flowers have a trilocular ovary 

 bearing a common style. The upper parts of the leaves wither while the basal 

 portions become swollen and fleshy and stored with reserve materials ; the scar at 

 the upper part of each scale marks the place of separation of the leaf- blade. The 

 :iunual course of development is essentially similar in other bulbous plants. The 

 vegetative period is restricted to a few montlis, while during the cold or, in the 

 numerous bulbous plants of warm-temperate climates, the dry seasons, the bulb is 



Fio. 7t)S. — Dracanna draco. The Dragon Tree of Laguna in the Canary Islands. 

 (From Chun, Atis den TUfen des Wellmeeres.) 



protected by its subterranean situation. Aloe, a gentis of African plants con- 

 taining many species (Fig. 767) may be mentioned as an example of an arborescent 

 member of the Lilieae. 



Dracacnn (Fig. 768), an arborescent form which attains a great age and a 

 characteristic appearance, together with the similar genera, Cordyline and Yucca, 

 belong to the Asparageae. To the same sub-family belongs Smilax (Sarsaparilla), 

 a shrubby plant of warmer countries, climbing by the help of tendril -like 

 emergences at the base of the petioles. Other examples are Asparagus with 

 bunches of phylloclades (p. 26) in place of leaves, Convallnria (Fig. 34), 

 Maianthemum, Polygonatum, and Paris quadrifolia (Fig. 769) ; the latter bears 

 whorls of four leaves, sometimes 3-6 leaves. All these plants have creeping rhizomes 

 bearing scale -leaves ; either the apex of this rhizome grows annually into the 

 erect shoot bearing the foliage leaves and inflorescences, while the growth of the 

 rhizome is continued by a lateral branch {Polygonatum, Fig. 23), or the rhizome 



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