DISTRIBUTION OF THE MOEE PEOMINENT NATUEAL OEDEES. 273 



of Chusquea abietifolia, imported from Jamaica, flowered at Kew the same season as 

 the plants of this grass generally in the island itself. 



The genera Yucca, Basylirion, and Nolina are polycarpic ; the second has apparently 

 strictly dioecious flowers, while the last is polygamously dioecious, both being in this 

 respect quite exceptional in the order Liliaceae. 



With regard to the number of species, particularly of the genus Agave, and their 

 local distribution, our information is exceedingly meagre. From the large number of 

 forms now cultivated in this country, it is evident that the genus is very diversified, 

 presenting distinct groups of species, the majority of which, however, are only known 

 from their foliage. But as mere numbers do not affect the main issues, this circum- 

 stance is of little consequence from a geographical stand-point. With regard to the 

 distribution within our limits, we have no knowledge of any species of Yucca, Nolina, 

 Basylirion, or Beschorneria south of Guatemala, and the records of these genera, as 

 well as of Furcrcea and Agave, south of Mexico, are extremely few. It seems impro- 

 bable that the two last genera do not exist in Nicaragua and Costa Eica, yet we have 

 no evidence of their existence in these countries. Possibly we may have overlooked 

 allusions to them in books of travel, or failed to make a note of them in consequence 

 of not appreciating their importance at the time. Seemann * enumerates Furcrcea 

 tuberosa from the slopes of the Volcan de Chiriqui, and F. gigantea from the Island of 

 Cacagual, Darien. The former was collected by Mandon in open situations, at 

 2600 metres, near Sorata, Bolivia, and we have seen specimens of it from Venezuela 

 and New Grenada ; but it is commonly cultivated for its fibre and readily colonizes, 

 hence it is difficult to determine where it is really indigenous. Martiusf mentions 

 that it has been cultivated and widely spread ever since America was discovered, and 

 that it is impossible to fix its origin ; while of Agave americana he says, " nullibi earn 

 vidi efferatam." Furcrcea cubensis, he suggests, may also be an introduced plant in 

 Brazil. Wagner J states that Agave americana is a characteristic plant of the oak and 

 alder region of Chiriqui, from 4200 to 8000 feet ; but this he may have confused with 

 the Furcrcea mentioned by Seemann. Plants of this type in the West Indies are — 

 Agave americana, general ; A. sobolifera, A. spicata, and Furcrcea cubensis, common ; 

 F. gigantea, Antigua and French Islands ; and Yucca aloifolia in Jamaica and Antigua §. 

 Both Agave americana and Furcrcea gigantea have established themselves in the 

 Mauritius, and the latter also in Eodriguez and Madagascar. These, then, are practi- 

 cally all the southward and eastward extensions, though there may be one or two more 

 species. In the Atlantic States of North America there are four species of Yucca, one 

 of Nolina and Agave virginica, mostly inhabiting sandy districts near the sea. 



* Botany of the Voyage of the 'Herald,' p. 216. t Mora Brasiliensis, iii. 1, p. 188. 



t Petermann's Geographische Mittheilungen, 1863, p. 294. 



§ Grisebach, « Flora of the British West-Indian Islands,' and ' Catalogus Plantarum Cubensium,' and Egger's 

 ' Flora of St. Croix and the Virgin Islands.' 



