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genera of the cactus family. The tall columnar forms belong 
to the genus Cerezs or its near relatives. In house no. 6 of the 
conservatories nearby will be found large specimens of a genus 
closely related to Cereus. This is Carnegiea gigantea, of Arizona 
and Sonora, the giant cactus or sahuaro. t the northerly end 
of this central bed are other cactus forms. Here will be found 
large plants of Gunnison’s hedge oe will at once attract 
in usually spiral rows. Some of these are especially attractive 
in flower or in the equally showy fruit. In this same large bed 
will also be found plants of the Spanish bayonet, Yucca aloifolia; 
the desert palm, Neowashingtonia; and the queer desert plant Fou- 
guieria; together with some desert forms of the pine-apple family. 
Forming a large part of the central bed is the collection of 
century plants, members of the genus Agave. In these instead 
of the thickened stems it is the thickened leaves which serve the 
purpose of storage organs. They too present a great diversity 
in form but not to so great an extent as the cactus family. The 
sisal hemp plant will be found here. In this, known as A gave 
rigida, the margins of the leaves are smooth, there being no 
spines whatever. In other species the marginal spines are large 
and form an effective armament for the plant. Some form dense 
rigid rosettes, a condition especially noticeable in Queen Victoria’s 
century plant, while in others the growth is more open, well 
shown in the largest specimen in the bed, occupying its center. 
This is the American century plant, Agave americana. 
A description and illustration of this plant were published in 
the May number of this JourNaL. At that time the flowering 
stem or ‘pole’ was but just making its appearance above the 
leaves. The illustration accompanying the present article shows 
