272 APPENDIX. 



member of the order, which presents its highest development in tree-like puyas of the 

 Cordilleras of Chili. 



The Agave and Yucca type. 



Plants of this type, belonging to the orders Amaryllidese and Liliaceae, are so 

 numerous and so specially characteristic of Mexico and the countries immediately to 

 the north as to demand separate consideration. The genera are Beschomeria, Agave, 

 and Furcrcea belonging to the former order, and Yucca, Nolina, and Dasylirion 

 belonging to the latter order. These genera are all peculiar to America, and a careful 

 examination of their present distribution seems to indicate that the outlying species 

 have spread from the Texano-Mexican region, taken in a wide sense, that is, including 

 New Mexico and Arizona. Of course it does not necessarily follow that because the 

 species of a genus are now most numerous in a certain region the genus originated 

 there ; but the majority of the outlying species of the genera under consideration are 

 also natives of the Texano-Mexican region, thus strongly favouring the presumption 

 that such was the case in this instance. Moreover, these plants, though belonging to 

 distinct natural orders, have the same general habit of growth, and long, rigid, fleshy 

 or dry leaves, crowded on usually very short stems, and relatively large inflorescences. 

 They differ greatly in stature, from two or three feet to sixty or occasionally taller. 

 The trunk of Furcrcea gigantea attains a height of three or four feet, while the flower- 

 scape is twenty-five to thirty feet. The tallest, however, is Furcrcea longceva, which 

 forms an unbranched trunk forty to fifty feet high, surmounted by a large dense crown 

 of leaves ; and its inflorescence is thirty to forty feet high, making altogether a height of 

 nearly 100 feet. These and some of the larger species of Agave are next to palms in size 

 among monocotyledonous plants. The species of Furcrcea and many of Agave, although 

 attaining a great age, flower only once (are monocarpic) and then die. In this they 

 resemble some of the palms ; the talipot (Corypha umbraculifera) and the wine-palm 

 (Caryota urens) for examples. On the authority of Karwinski *, who discovered the 

 gigantic Furcrcea longceva in the mountains of Oaxaca among stunted oaks and arbutuses 

 at altitudes of 9000 to 10,000 feet, this species requires a very long period before it 

 can put forth flowers — about 400 years, according to the traditions of the natives. 

 This is probably a greatly exaggerated period ; yet several instances are on record of 

 plants of this class having been cultivated in Europe for eighty to a hundred years 

 before producing flowers. But the flowering of these perennial monocarpic plants is a 

 most interesting and phenomenal event. It has been observed that all the individuals 

 of certain monocarpic species of palm and bamboo flower the same season throughout 

 very extensive districts. How far this is influenced by recurring stimulating climatal 

 conditions, or how far it is an inherent constitutional action, limited in its fulfilment, 

 is uncertain ; but, as bearing directly on the subject, it may be mentioned that plants 



* Nova Acta Nat. Cur. xvi. (1833) p. 665. 



