444 CACTUS TRIBE ; NIGHT-BLOWING CEREUS. 



unknown until recent years. No distinction can be traced be- 



c tween the calyx and 



corolla ; for the flow- 

 ers branch off directly 

 from the stem, and 

 its cylindrical axis 

 is covered with scale- 

 like coloured bracts, 

 which at the upper 



FIG. 1<>3. PARTS OF FLOWER OF CACTUS TUNA. A, , ., 



thickened axis, bearing the Stamens, a, the style, b, P^rt gradually pass 



and stigma, c ; and enclosing the ovariura, d. B, vertical j nto thm delicate D6- 

 section of ovanum. C, transverse section of ditto. < \ 



talline leaves, which 



unfold, tier after tier, from within each other, adhering by their 

 lower ends so as to produce a firm fleshy tube. From the inte- 

 rior of this tube, spring a number of rows of slender stamens. 

 The ovarium is situated in a cavity within the apparent stalk of 

 the flower; and contains a considerable number of ovules, 

 attached to parietal placentae. The style is a single column, 

 springing from the top of the ovarium ; and, after rising above 

 the anthers, it divides into a star-shaped set of stigmas, equal in 

 number to the placentae. The beauty of the flowers is usually 

 very short-lived ; some of them only last for a few hours. One 

 of the most splendid species is the Cereus grandiflorus or night- 

 blowing Cereus, the blossoms of which begin to expand about 

 6 or 7 o'clock in the evening, and are fully blown about 

 midnight ; but, by 3 or 4 in the morning, they are quite 

 decayed. During its short continuance, however, there is 

 scarcely any flower of greater known beauty. The perianth, 

 when open, measures nearly a foot in diameter ; the outer 

 leaflets are of a dark brown colour, the inner ones are of a 

 splendid yellow, gradually shaded, toward the centre of the 

 flower, into a pure and brilliant white. When several of these 

 magnificent flowers, therefore, are open at once upon a single 

 plant, they seem like stars shining out in all their lustre, veri- 

 fying the poet's declaration that 



Darkness shows us worlds of light 

 We never see by day." 



