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sisal plant (Agave sisalana); and the common century 
plant (Agave americana). The first two are decorative 
and curious; from Agave sisalana is manufactured the sisal 
hemp of commerce; the last, Agave americana, is well 
known, and it is from the sap of related species that the 
Mexican drink “‘pulque” is obtained by fermentation. 
It is popularly believed that the century plants flower but 
once in a hundred years, and then die; it is true that the 
plant dies when done blooming, but it blooms at a much 
earlier age than a century, sometimes when but eight or ten 
years old, itis said. Thecollection of West Indian Agaves is 
especially rich in species. A curious desert plant among the 
century plants on the side bench is called by the natives of 
Mexico, its native country, “‘huariqui” (Ibervillea sonorae) ; 
during the rainy season green stems arise from these large 
woody plant-bodies, which at other times remain in a 
resting condition. 
A group of the dracaena family may be found in the 
central portion of this house. This comprises members 
of the genera Aloe, Yucca and Dasylirion. A group of 
cacti may also be seen here, the most imposing figure of 
which is the giant cereus, Carnegiea gigantea, known as 
“sahuaro”? by the Mexicans and Indians of its native 
country, Arizona and Sonora. The plants here shown 
were obtained by an expedition sent to those regions by 
the Garden in 1902, and are the largest specimens in culti- 
vation in the east. Several large specimens of the hedgehog 
cactus, secured at the same time, form part of this group; 
the Indians in the desert often secure a supply of drinking 
water from these plants by cutting off the top and macer- 
ating the interior substance. 
Houses Nos. 7 and 8 are wholly occupied by the cactus 
family. The collections here have been greatly enriched 
and enlarged in the past few years by extensive explora- 
tions made in South America, in cooperation with the 
Carnegie Institution, and from other sources. These col- 
lections, the richest in species in the world, have been 
