298 PHYLUM XIV. AXTHOPHYTA 



stigmas. The ripened pistil tightly encloses the seed, 

 forming the "grain" or ''caryopsis." 



542. Maize (Indian Corn) has a solid (not hollow) 

 stem and its spikelets are diclinous, the staminate form- 

 ing a branching inflorescence at the top of the stem, the 

 pistillate being crowded upon the lateral ''ears," which 

 terminate short lateral branches, whose numerous 

 crowded leaf sheaths form the ''husks." The staminate 

 spikelets are in pairs (one sessile, the other stalked), 

 and each is two-flowered. The pistillate spikelets are 

 also in pairs, but here there is only one flower in each. 

 The styles ("silks") are long, and bistigmatic. The 

 corn "kernel" is the ripened ovary with its tightly 

 fitting single seed. 



543. The Sedges (Family Cyperaceae) are a family 

 of widely distributed, somewhat more primitive, grass- 

 like plants that differ in vegetative structure from the 

 Grasses in that the leaves are three-ranked, instead of 

 two ranked, and the stems solid instead of hollow. The 

 spikelets more often have the bracts spirally arranged, 

 only a few genera having them two-ranked as in the 

 grasses. The axillary flower consists of a tri- or a bicar- 

 pellary pistil, six, or more often three, stamens, and a 



perianth of two ternate whorls of 

 narrow segments, or bristles or want- 

 ing. The ovary wall is not grown 

 fast to the single seed. 



544. Amaryllis {Iridales). In the 



Amaryllis the flower is Lily-like with 



Fig. 171.— Amaryllis ^ ^^^^^ dcvclopcd perianth of six equal 



petaloid segments (sepals three, petals 



three), six stamens, and a tricarpellary, long-styled pistil, 



whose ovary is overgrown by the receptacular cup which 



carries up the perianth and stamens, so that the ovary 



