272 



THE GRASSES. 



The InJlo7^escence is variously deyeloped in these speci- 

 mens. Generally it ai3pears as in Spear Grass (Fig. LXXII), 

 a branching pyramidal bouquet — a 'panicle, differing from a 



raceme inasmuch as the 

 branches are branched 

 again. It is well to ob- 

 serve whether the branches 

 are grouped in 5s, 2s, or 

 Is. In other specimens the 

 inflorescence is contracted 

 into a spike or a spike-like 

 panicle. The flowers are 

 collected into little clusters 

 called spikelets. Let us 

 here take up a spikelet of 

 Spear-gTass (Fig. LXXII, 1), 

 which we may study as a 

 type of all. It is scarcely 2" 

 in length, ovate-lanceolate 



Fig LXXII — Poa pratensis (a depauperate specimen, for the branches are usuaUy 

 in 5s) • 1, a spikelet with 2 glumes and 4 flowers ; 2, a single flower ; 3, ovary and 

 feathery stigmas; 4, ripe kernel enclosed in the 2 pales ; 5, Poa debilis ; g spikelet. 

 3-flowered ; /, a flower ; 6, a spikelet of Phldum pratense : a, the 2 awned glumes ; 

 b, the 2 pales and ovary. 



in outline. At the base are 2 chaffy bractlets— the glumes 

 (g). Within and above the glumes are 4 flowers (more or 

 less), alternate, imbricated when closed. Such is a spikelet. 



