DEVELOPMENT OF PLANTS 



403 



sporophylls arranged in a compact inflorescence that assumes a 

 spike-liice structure at the tip of the stem.* The sporophylls are 

 protected until mature by modified sheathing leaves (Fig. 280, A). 

 Each flower in the upper portion of the spike contains only two 

 or three stamens supported upon a short stalk, which is asso- 

 ciated with hair-like outgrowths (Fig. 280, B), while the lower 

 flowers of the spike bear a single pistil each (Fig. 280, C), which 



Fig. 280. Fig. 281. 



Fig. 280. Inflorescence and fruit of Typha: A, inflorescence — 6, pro- 

 tecting bracts curving away from the sporophylls; mi, region of staminate 

 flowers; mg, region of pistillate flowers. B, staminate flower consisting of 

 two stamens sessile upon a short stem. C, pistillate flower of one carpel — 

 s, stigma; 0, ovary containing a single ovule. D, appearance of A in the 

 fall — mi, region occupied by staminate flowers; mg, the pistils have increased 

 greatly in size during the ripening of the seed. 



Fig. 281. The mature fruit of Typha: s, remains of the stigma; 0, ovary 

 p, elongated pedicel bearing numerous hairs. Compare Fig. 280, C. 



consists of a large flat stigma, style and ovary containing a single 

 ovule and supported upon a hairy stalk or pedicel. Note the 



