24 



FAMILIES OF FLOWERING PLANTS. 



Fig. 19.— Barnyard grass (Panicnm 

 Crus-fjaUi). (After Britton and Brown, 

 111. Fl. Northern U. S.) 



gions to the lofty arborescent bamboos of the tropics. The inflores- 

 cence consists of what are technically called apikelets^ each of which 



is made up of small imbricated 

 chafl'y scales. Some of these scales 

 are empty; others enclose the sta- 

 mens, usually three in number, and 

 the pistil; and each of these flower- 

 bearing scales usually encloses an 

 additional, very slender scale known 

 ^^ as thejt^a^di^. Every individual floret 

 thus consists of the essential oro;ans 

 of reproduction, surrounded by two 

 protecting scales; one or more of 

 the florets are borne to2[;ether on a 

 slender axis, forming a spikelet; 

 while the innumerable spikelets may 

 be clustered together in a spike, as 

 in timothy, or borne in an open 

 branching panicle, as in red top, 

 Kentucky blue grass, and many 

 other species. The leaves of these plants are so well known that the 

 term grass-like is common as a standard of comparison. At the junc- 

 tion of leaf and stem, Avhere the base 

 of the leaf usually forms a complete- 

 ly enwrapping sheath, will be noticed 

 in most cases a peculiar membranous 

 ring or protuberance; this is called 

 the ligule, a name derived from its 

 suggestion of a little thong or strap, 

 and it is an indisputable proof, if 

 present, that we have a grass and 

 not a sedge or rush before us. The 

 grass stem or ciihii is hollow, ex- 

 cept at the joints. 



Little need be said of the value 

 of grasses for forage and pastur- 

 age; indeed they furnish nine-tenths 



of the subsistence of domesticated fig. 20.— Forked Beard-grass (Andro- 



, , . . , 1 -ii ii imgoii fiircatits). (After Britton and 



herbivorous anuuals, and with the Browa, 111. fi. Northern u. s.} 



