48 FUNDAMENTALS OF AGRICULTURE. 



The pollen is produced in stamens also arranged in a 

 cone. Examples are pine, spruce, cedar, cypress, 

 juniper, etc. The needle-leaved trees and some others 

 belong to this group. 



Kinds of Flowering Plants. The true flowering 

 plants are again divided, the one class possessing seeds 

 with but one seed leaf and with the parts of the flow- 

 ers mostly in threes, the other with two seed leaves 

 and the parts of the flowers mostly in fives. The first 

 class has its leaves with the veins mostly all parallel, 

 while in the second class the veins are mostly net-like 

 or diverging. In the trees belonging to the first 

 group the trunk does not regularly increase in thickness 

 as it gets older, while in the second class the wood in- 

 creases in thickness each year by the so-called annual 

 rings. All the grasses, palms, lilies, orchids, etc., be- 

 long to the first group, while to the second belong most 

 of the remaining cultivated plants; e. g., fruits such as 

 apple, pear, peach, orange, persimmon; most of the 

 vegetables, as beet, potato (sweet and Irish), turnip, 

 cabbage, artichoke, carrot, etc., the various nuts, and 

 practically all timber trees except the needle-leaved 

 ones. 



Stages of Plant Development. In the develop- 

 ment of a plant from the seed we can distinguish sev- 

 eral stages. Usually three are considered, viz., ger- 

 mination, growth and maturity. In reality the one 

 grades into the other, by such gradual degrees, that the 

 distinctions are mostly somewhat artificial. Growth 

 may occur in all three stages, and is always present in 

 the first two. As was pointed out a seed is simply a 

 young plant, with development arrested, surrounded 

 by or containing sufficient food to give it a start, until 

 it is far enough developed to manufacture enough food 

 to supply its own needs. 



Parts of a Seed. In a ripe seed we can distinguish 

 within the seed coat the young plant, often called the 

 embryo, it being often surrounded by a layer of cells 

 serving to feed it when it grows, the endosperm. In 



