CLASSIFICATION. 
127 
A Genus comprehends one or more species, grouped together on 
account of some resemblance in situation, proportion, and connexion 
of the organs which constitute the flower. Any one species of a 
genus may be regarded as a type or example of the others; we may 
easily refer species which we have not studied to their proper genus, 
by a knowledge of any one species of that genus. Some genera 
appear to be distinctly marked by nature ; the various species of the 
rose form a beautiful genus which is known to all, although every 
one might not be able to describe it to others in such a manner as 
to be understood; it is chiefly distinguished by its urn-shaped and 
fringed calyx. 
The generic names of plants are derived from various circum¬ 
stances ; in some cases from a peculiarit)^ in the form or colour of 
the corolla, or some property of the plant; and some are named from 
distinguished persons. Thus Iris (flag) is named from Iris the rain¬ 
bow, on account of its various shades of colour. Digitalis (fox¬ 
glove) is named from digitus , a finger, on account of the shape of 
its corolla, which is like the finger of a glove. Convallaria (lily 
of the valley) is named from a Latin word convallis , signifying, in 
the valley. Teucrium (germander) is named in honour of Teucer, 
a Trojan prince. The English name, germander, is supposed to 
have originated from the word Scamander, the name of a river of 
ancient Troy. The name of the great Linnaeus is commemorated 
in a beautiful and modest flower, called the Ldnncea borealis* 
Specific names are adjectives; generic names are nouns. The 
specific name sometimes indicates the number of leaves, as orchis 
bifdlia , (bifolia, signifies two leaves;) or the colour of the corolla, 
as viola tri-colour , (three-coloured violet;) or the form of the root, 
as soLANUM tuberosum , (with a tuberous root.) Specific names are 
often derived from the names of persons; thus a species of Origa¬ 
num is named tourrnefortii , after its discoverer Tournefort. 
The system of Linnaeus may be illustrated by the following com¬ 
parison as, 
Individual persons compose Families, 
Families “ Towns, 
Towns a ’ Counties, 
Counties u States. 
Individual plants compose Species, 
Species “ Genera, 
Genera “ Orders, 
Orders “ Classes. 
Thus, as individual persons are the real existences which make 
up a state; so are individual plants the real existences which com¬ 
pose classes ; the words town and county, genus and order, being 
general terms used to designate certain circumstances of these men 
and plants. 
Natural Families. 
After having analyzed a number of plants, you will begin to ob¬ 
serve a striking resemblance in many genera, and your own minds 
will suggest the propriety of arranging them into groups, without 
any reference to the artificial class or order where they may have 
* Borealis , signifying northern , has reference to the situation of the country which 
S ave birth to Linnaeus. The Linnaea borealis is not uncommon in New England, and 
as been found on an island in the Hudson^ near Troy. 
What is a genus 1 —A knowledge of one species enables us to recognise all other 
species of the same genus—Derivations of generic names—Iris—Digitalis—Teucrium 
—Linnaea borealis—Specific names—Natural families. 
