ORGA.NS OF EEPEODUCTION. 



193 



Sedge Order. It is a spike with a few flowers, and these desti- 

 tute of a true calyx and corolla, their place being occupied by 

 j)alece or pales {fig. 379, ps, pi), and the whole inflorescence 

 surrounded at the base by one or two empty bracts {glumes), 

 gl, gl. These spikelets may be either arranged sessile on the 

 primary axis or rachis ( fig. 392). as in 

 Wheat, or they may be placed on a more or 

 less branched axis, as in the Oat {fig. 393). 

 The spikelets of plants of the Sedge Order 

 present certain peculiarities, but they are 

 essentially of the same nature as those of 



Fig. 394. 



e. The Cone. — ^This is a kind of spike, 

 found especially in cone-bearing plants, as the 

 Larch, Pine, and Fir {fig. 394). It is com- 

 posed of pistillate flowers, each of which has 

 at its base a persistent woody scale or bract. 



f. The Sirobilus or Strobile. — This is a 

 kind of spike with pistillate flowers, each of 

 which has a membranous bract or scale at its base, 

 in the Hop {Humulus Licpuhcs) {fig. 395). 



All the kinds of indefinite inflorescence at present described 

 owe their essential characters to the flowers being sessile upon an 

 elongated axis. We now pass to describe others, in which the pri- 

 mary axis is more or less branched, and the flowers consequently 

 situated upon stalks. The simplest of these is the Raceme. 



Fig. 395. Fig. 396. 



Fig. 394. Cone of Hem- 

 lock Spruce (Abies 

 canadensis). 



It is seen 



Fig. 395. Strobile of the Hop {Humulus 



Lupulus). Fig. 396. Raceiae of a 



species of Cherry (Cerasus). 



g. The Baceme. — This name is ap- 

 plied to that form of inflorescence 

 in which the primary axis is elon- 

 gated, and bears flowers placed on 

 pedicels of nearly equal length {fig. 

 396). 



It only differs from the spike 



