800 HOW CROPS GROW. 
ter-cress, etc., are termed Cruciferous plants, because their 
flowers have four petals arranged like the four arms of a 
cross, (Latin, cruz). 
The flowers of a large natural order of plants are ar- 
ranged side by side, often in great numbers, on the expand- 
ed extremity of the flower-stem. Examples are the thistle, 
dandelion, sun-flower, artichoke, China-aster, etc., which, 
from bearing such compound heads, are called Composite 
plants. . 
The Coniferous (cone-bearing) plants comprise the 
pines, larches, hemlocks, etc., whose flowers are arranged 
in conical receptacles. 
The flowers of the carrot, parsnip, and caraway, are ar- 
ranged at the extremities of stalks which radiate from a 
central stem like the arms of an umbrella; hence they are 
called Umbelliferous plants, (from wmbel, Latin, for little 
screen). 
§ 2. 
THE FRUIT 
THE Frouir comprises the seed-vessel and the seed, to- 
gether with their various appendages. 
THE SEED-VESSEL, consisting of the base of the pistil in 
its matured state, exhibits a great variety of forms and 
characters, which serve, chiefly, to define the different 
kinds of Fruits. Of these we shall only adduce such as 
are of common, occurrence and belong to the farm. 
The Nut has a hard, leathery or bony shell, that does 
not open spontaneously, Examples are the acorn, chest- 
nut, beech-nut, and hazelnut. The cup of the acorn and 
the bur of the others is a sort of fleshy calyx. 
The Stone-fruit or Drupe is a nut enveloped by a 
fleshy or leathery coating, like the peach, cherry, and plum, 
