154 



PATAGONIAN EXPEDITIONS I BOTANY. 



are hydrophilously fertilized. They are then submerged again and ripened 

 under water. Fruit long-cylindric, crowned by the perianth. 



V. SPIRALIS Linn. 



In the warmer parts of both worlds, and in temperate North America. 

 In a brook by Rio Chico de Sta. Cruz, Patagon. (J. B. Hatcher, the young 

 plants on March 27, 1897). 



Family 10. GRAMINE^E. The Grasses. 



Herbs (or rarely in the tropics woody plants), with terete hollow stems 

 and nodes solid (the whole stem is solid in a few), and with narrow 2- 

 ranked parallel-veined leaves, sheathing at their base and the sheaths split 

 in front and liguliferous at their top. 



Flowers glumaceous and collected in 

 spikelets, each having i -several flowers. 

 The spikelets arranged in compound in- 

 florescences, as racemes, or spikes, or con- 

 densed or lax panicles. 



Analysis of a spikelet, proceeding from 

 below upward (Fig. 30) : 



(i) General part, for the whole spikelet : 

 Glumes, i, 2, or 3; mostly 2, equal or 



Poakergudensis. Spikelet and its diagram. Unequal I often Called " empty glumes "; 



gi, g, glumes ; f g , floral glumes ; /, /, paieae. here mostly called simply "the glumes." 



(2) Particular part, belonging to the individual flowers : 



Palets or glumelles, normally 2 for each flower, viz. 



(a) the outer or lower palet, often awn-bearing, and commonly termed 

 the "flowering-glume" or "floral glume," which may be conveniently 

 transformed into the single term, floriglume. 



(b} the upper or inner palet : it is usually thinner than the preceding, is 

 2-keeled, not awned ; and is usually next the axis, rachilla, of the spikelet. 

 We may call it the palea. Callus or anthopodium is an enlargement of 

 the rachilla below the flowering glume. 1 



Also (c] Lodicules, i, 2, or 3 minute 'scales,' enclosed by the palets, 

 placed either anteriorly, or laterally, or posteriorly. 



1 The German terms are : (spikelet) ahrchen ; (empty glume) hiillspelze ; (floriglume) deck- 

 spelze ; (palea) vorspelze. 



