LILY FAMILY 



Stamens.— Six, shorter than the perianth. 

 Ovary. — Oblong; stiginas' three, sessile. 

 Capsule. — Oblong, three-lobed, many-seeded. 



Yucca is a genus comprising a few liliaceous plants native to the 

 semi-arid portions of the United States and Mexico. A few 

 species are hardy at the North; Yucca glaika, whose home is 

 the Rocky Mountain region and the Western Plains, flowering 

 early in June; and Yucca filamentosa, native to our Southern 

 States, are the two most satisfactory in our Northern gardens. 



The effect of a blooming bed of Yuccas, when properly placed, 

 is particularly good; but the stiff tropical habit of the plant does 

 not harmonize with softer vegetation. 



If one would know the Yucca in its best estate, one must see its 

 blooming panicles by moonlight, for it is the moon's own flower. 

 The mass of nodding bells, comparatively dull and opaque by 

 day, by moonlight are transfigured and fairly radiate a soft, 

 silvery lustre impossible to describe. 



One of the most extraordinary cases of the mutual dependence 

 of an insect and a flower, says Campbell's "Text Book of Botany," 

 is found in the species of Yucca known by the common name 

 of Yucca filamentosa, native to the southern Atlantic States, 

 and common in gardens. This species depends for its pollina- 

 tion upon a small nocturnal moth of the genus Pronuba. This moth 

 deposits its eggs within the ovary of the Yucca, and the larvae feed 

 upon the young seeds. In order that the flower may be fertilized 

 so that the ovules will develop into the seeds necessary to nourish 

 the larvae, the moth deliberately collects a quantity of pollen, 

 which it pushes into the cavity at the apex of the stigma, thus 

 insuring the fertilization of the ovules. In this species of Yucca it 

 is absolutely necessary, in order that seeds may be formed, for the 

 moth to do this, and if the insect is absent the flowers will all re- 

 main sterile'. The larvae of the Pronuba do not destroy all the 

 seeds; a considerable number remain unijjjured and mature in 

 the ripe capsule. 



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