130 



OKDER CXLI. EQTJISETACE.E. 



the next, usually with a membranous ligule between the base o: 

 the leaf and sheath. Flowers in spikes, racemes or panicles 

 usually perfect, in 1 -many-flowered spikelets, composed of glume 



Fig. 42. 



Fig. 47. 



like bracts in 2 rows. Outer bracts (glumes), 2, rarely 1, often 

 unequal ; the inner 2 immediately inclosing each flower (palece), 

 alternate. Perianth none, or consisting of very small, membran- 

 ous scales (syuamulae). Stamens 1 6, commonly 3. An- 

 thers versatile. Ovary 1-celled. Styles 2. Stigmas 2, 

 feathery. Fruit a caryopsis. 



A very large and most important order, diffused through all parts of 

 the world in the greatest abundance. The herbage furnishes food for 

 cattle and other herbivorous animals, while their seeds, known as the 

 Fig. 43. Cereal Grains, form the most important article of human sustenance. 

 None are poisonous, except a single species, the Darnel Grass (LoUum). 

 The poisonous properties of Ergot are caused by a parasitic fungus. The stems 

 of many of the species afford sugar, which is most abundant in the different 



species of Sugar-Cane (Saccha- 

 rum), and is found also in the 

 Indian Com (Zed). Among the 

 grains, the most important are 

 the Oat (Avena), fig. 41, the 

 Wheat, Eye, Eice, Barley, and 

 Maize. The most valuable kinds 

 for grazing purposes are Agros- 

 tis (Red-top), Pbleum (Timothy 

 Herds-grass), and other mea- 

 dow and pasture Grasses com- 

 prising especially various species 

 of Poa and Festuca. In flg. 42 

 is represented Eragrostis megas- 

 tachya, illustrating one of the 

 most common forms of Grasses. 

 In flg. 43 we have a inany- 

 flowered, awnless spikelet of a 

 Glyceria ; and in flg. 44, a many- 

 flowered spikelet of Bromus, 

 with awned paleae. Panicum la- 

 tifolium, flg. 45, is a representative of another tribe, whose peculiar structure is 

 well illustrated in the spikelet of Panicum Crus-Galli, flg. 46, where we have 

 two flowers, one of which only is complete, the other being reduced merely to 



Flg. 44. 



Fig. 46. 



a pair of palea, so that each spikelet has four palese, two of which are, in this 

 case, awned. In flg. 47 is represented Elymus Virginicus. a native example of 

 the tribe to which the Wheat, Eye, and Barley belong. 



Fig. 45. 



SEKIES II CRYPTOGAMIA. 



Plants without proper flowers, containing stamens and pistils, 

 not reproduced by proper seeds containing an embryo, but by 

 spores or reproductive cells. 



CLASS III ACROGENS. 



Plants with a regular axis of growth, distinguished more or 

 .ess into root and stem, and usually into leaves also ; their struc- 

 ;ure made up of woody and cellular tissues, and the various ves- 

 iels found in higher plants ; the axis increasing in height and not 

 n diameter, and all growth taking place at the terminal bud of 

 ,he stem or branch. 



OKDER CXLI. Equisetaceae. 



Leafless plants, with jointed, grooved stems, either simple, or 



with verticillate branches, which are hollow and closed at the 

 joints, each terminating in a dentate sheath. Inflorescence a 

 lense, cylindric, terminal spike, or strobile, composed of peltate, 

 icxagonal scales ; each scale with several thecse or spore-cases 

 .ttached to its under surface, opening longitudinally. Spores 



numerous, with 4 elastic threads, called elaters, wrapped round 



them. 



An order consisting of a single genus, Eqnisetum (Scouring Bush, Pipes, 



Horsetail), found in damp grounds in all parts of the world. 



