CRYPTOGAMOUS OR FLOWERLESS PLANTS. 



493 



especially in the few instances where it is solid, as in the Maize, 

 and more largely in the Sugar-Cane (Saccharum officinarum), 

 which affords the principal supply of this article. 



Series II. CRYPTOGAMOUS OR FLOWERLESS PLANTS. 



Plants destitute of proper flowers (stamens and pistils), and 

 propagated by spores instead of seeds (101, 109). 



CLASS III. ACROGENOUS PLANTS. 



Vegetables with a distinct axis, growing from the apex, with no 

 provision for subsequent increase in diameter (containing woody 

 and vascular tissue), and usually with distinct foliage (108). 



927. Ord, Episetaceae (the Horse-tail Family). Leafless plants ; 

 with striated, jointed, simple or 114 . 2 U4l 

 branched stems (containing ducts 



and some spiral vessels), which 

 are hollow and closed 'at the 

 joints ; each joint terminating in a 

 toothed sheath, which surrounds 

 the base of the one above it. In- 

 florescence consisting of peltate 

 scales crowded in a terminal 

 spike, or kind of strobile : each 

 with several thecce attached to its 

 lower surface, longitudinally de- 

 hiscent. Spores numerous, with 

 four elastic club-shaped bodies 

 (of unknown use, called elaters) 

 wrapped around them. Ex. 

 Equisetum. The epidermis of 

 Equisetum hyemale (Scouring 

 Rush) contains so much silex 

 that it is used for polishing. 



928. Ord, Filices (Ferns). Leafy plants ; with the leaves (fronds) 



FIG. 1141. Summit of the stem of Equisetum sylvaticum. 1142. Part of the axia of the 

 cone of fructification, with some of the fruit-bearing organs, shown magnified in Fig. 1143. 

 1144. A separate theea, more magnified. 1145, 1146. Spores with elaters, still more magnified. 



42 



1146 



