CLASSIFICATION OF PLANTS. 
455 
2. Gramina, Grasses.—These important tribes afford three-fourths, 
or four-fifths of the food of all nations. They were called by Lin¬ 
naeus, Plebii, or Commoners, because if not the most ornamental, 
yet amongst the most useful members of the vegetable community. 
3. Lilia. —The beautiful group of lilies, &c. were called by Lin¬ 
naeus Patritii or Patricians. 
4. Herbae, or herbs, were called Nobiles, or Nobility. 
5. Arbores , or Trees, he distinguished as Proceres, or Notables. 
6. Filices, or Ferns, were called Colonizers, because they are the 
first of the higher orders of the Vegetable Kingdom, which are found 
naturally growing upon spots occupied only by some of the succeed¬ 
ing grades. Their propagation is not by seeds, but by little bodies 
called Sporules, inclosed within cases named thecce ; the whole hav- 
ing the appearance of a kind of dust produced on the back of the 
fronds, and which is so light, that it is easily carried by the winds 
from one place to another, to incredible distances. 
7. Musci, Mosses.—The numerous tribes of this interesting fa¬ 
mily are very appropriately called Servi, or Servants, from the im¬ 
portant offices they perform in the world. They form soils on the 
most barren rocks, by the decomposition of many successive genera¬ 
tions, until it becomes of a sufficient depth to support the higher or¬ 
ders of Vegetation; when man comes with his implements of culture, 
and ventures to claim the soil as his own. Water mosses purify the 
water in which they grow, by absorbing the putrescent substances 
with which it may be corrupted, and by exhaling oxygen in ex¬ 
change. These plants are also increased by sporules, contained 
within an urn, placed at the top of a stalk, bearing on its summit a 
kind of loose hood called a calyptra, and closed by a lid. When the 
fructification is more advanced, the lid falls off, and the seeds are 
then kept in by means of a set of teeth or a fringe, placed around 
the mouth, which open in wet weather, and allow the seed to escape. 
8. Algae , Sea-weeds, &c. These were considered by Linnaeus as 
Vernaculi, or Bond Slaves, because although they are attached to 
certain matters, they derive no nourishment from them, but subsist 
chiefly, if not wholly, by atmospherical inhibition. The sea weeds 
are called flags, because when taken out of the water they flag or 
droop. These plants may be seen in their simplest state in the form 
of a green slime on the surface of stones exposed to constant moisture, 
on shady walls, and damp walks. Algae in a state of higher organi¬ 
zation clothe the rocks in the sea, where they form forests of con¬ 
siderable extent; and grow to an amazing size ; the Chorda filum 
being frequently found thirty or forty feet long; and the Macrocystis 
