BOTANICAL TERMS. 



41 



lieaf. 



Sheath : the .ower portion of the leaf surrounding the stem, 

 and split on the side away from the blade (Fig. 238). 



LiGULE : a thin upward projection from the top of the sheath. 



Fruit. 



This alwa3'"s a caryo^sis or grain. 



TYPES OF GRASSES. 



The following selection of Grasses will be found useful for 

 examination, as illustrating most of the variations in the 

 structure of these plants. 



1. Timothy. 



Note the close iutiorescence. Separate one of the component 

 pieces which will probably resemble Fig. 234. If fully 

 opened out it will resemble Fig. 235. Carefully dissect 

 and describe, making a floral diagram. The spikelet 

 here consists of a single flower. 



2. Red-Top. 



Note the open panicle (Fig. 236). Detach and dissect a spike- 

 let (Fig. 237), which in this plant also consists of a 

 single flower. Observe the difference in the size of the 

 inner bracts, and the three nerves on the larger one. 



3. Meadow-Grass. 



The inflorescence is here an open greenish panicle, but each 

 spikelet (Fig. 239) is compressed laterally and contains 

 from three to five flowers. Fig. 240 shows a single 

 flower. Note the delicate whitish margin of the lower 

 palet, and the thin texture of the upper one; also the 

 two teeth at the apex of the latter, and the five nerves on 

 the former. 



4. Chess. 



Here the spikelets (Fig. 241) are on long, slender, nodding 

 pedicels, and each contains from eight to ten flowers. 

 The glumes are different in size. Dissect out a single 

 flower (Fig. 242) and note the awn on the lower palet. 

 The upper palet at length grows fast to the groove of the 

 oblong grain. 



5. Oouch-Grass. 



In this grass the spikelets are sessile on opposite sides of a 

 zig-zag peduncle, so that the whole forms a sort of spike. 

 Each spikelet is four to eight -flowered, and there is but 

 one at each joint of the peduncle, the side of the spikelet 

 being against the stalk. Note the running root-stocks, 

 which cause the grass to be a nuisance difficult to get 

 rid of. 



k, 



f^ 



panic 





# 



culm- 



[?^ 



sheath 



spikelet 



glume 



palet 



Fiir. I'S'.i. 



Fiff. 240. 



Fig. 241. Fig. 242. 



