THE STRUCTURE OF PLANTS. 7 



it remains stationary, while from its lower end small fibrous 

 (thread-like) rootlets issue, protected by sheaths at the 

 points where they spring from the radicle. A representa- 

 tion of this kind of root will be found in Plate I. fig. 2, 

 p. 15, showing a root of wheat. 



These differences in the parts of seeds, manner of growth 

 in the root, and number of seed-leaves, must be remembered 

 as indicative of the two great classes to which the pea and 

 the wheat respectively belong. 



The vegetable kingdom, according to the Natural System 

 of Botany, is arranged in two great divisions or Sub- 

 Kingdoms, viz. 1. Phanerogamous or ' Flowering plants,' and 

 2. Cryptogenic or ' Flowerless plants.' The two classes of 

 division 1 — namely, Monocotyledons and Dicotyledons — 

 have been mentioned. The second division or third class 

 — namely, Cryptogams or Acotyledons (without seed-lobes) 

 — comprises flowerless plants. In the plants belonging to 

 this class are included many species of Australian vegeta- 

 tion, amongst which are the extensive families of ferns, 

 mushrooms, and mosses. The acotyledons, however, will 

 form the subject of a separate lesson. 



During this and subsequent lessons, occasional recapitulations should be made of 

 the botanical terms used and their signification. Only those words are given which 

 are absolutely indispensable. 



LESSON II. 

 THE STEUCTUEE OF PLANTS. 



In germinating, — starting into active life, — the seed, as we 

 saw in the previous lesson, developed two parts, the one 

 pointing upward (plumule), the other downward (radicle). 



