2044 



A TEXTBOOK OF THEORETICAL BOTANY 



The chief genera of the Agaveae are Agave, Furcraea, Beschorneria and 

 Doryanthes. Agave (see Fig. 1057) is a large genus with about 250 species 

 occurring in tropical America and the southern United States. The stem is 

 short and stout and at the top is a large mass of long, rather fleshy, stiff leaves 

 generally covered with a wax. Only two or three new leaves are produced 

 each year. The plants live for a long time and may continue to grow for a 

 long period up to 100 years before producing an inflorescence. During this 

 time the plant stores up a vast reserve of food. Finally an inflorescence 

 develops. It is often a gigantic structure, usually a compound panicle, 

 reaching 20 or more feet in height and bearing many flowers. In some plants 

 many, or indeed all, ofthe flowers may be replaced by bulbils which serve for 

 vegetative propagation. During its formation the rise of sap is so rapid that 

 in Mexico a drink can be readily obtained by cutting off an inflorescence 

 and collecting the sap as it runs out of the cut tissue. As much as 1,000 

 litres can be gathered from a single plant. This juice is fermented and forms 

 a powerful drink, pulque. The genus Furcraea contains twenty species also 

 distributed in tropical America. The plants are similar in appearance to 



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Fig. 1984. — Dasylirion hookeri. Plant with a large stem 

 tuber covered with thick bark, and linear, fibrous leaves. 



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