172 
NATURAL FAMILIES. 
food, are the carrot, parsnip, celery, and parsely ; the aromatics 
are dill, fennel, sweet cicely, caraway, and coriander ; and 
among the poisonous plants, are the conium, (poison hemlock.) 
water-parsnip, and the cicuta, (water-hemlock.) 
Class 13. 
Dicotyledons. Corolla polypetalous, stamens hypogenous, 
(under the germ.) 
In this class the principal family is the Cruciform ( Cruciferce .) 
In these plants we find such flowers as have a calyx consisting 
of four leaves, and a corolla composed of four petals ; each petal 
is fastened to the receptacle or bottom of the calyx by a nar- 
row part called a claw ; the whole exhibiting the form of a cross ; 
hence the term cruciform, from crux , a cross. In the centre 
of the flower is a single pistil, long and cylindrical ; the stigma 
is oblong and divided into two parts, which are reflexed or bent 
back on each side. Each petal is placed between two leaves of 
the calyx ; this alternate position is always seen in flowers 
where the number of petals equals the number of leaves of the 
calyx. 
The cruciform flowers have six stamens, two of which stand- 
ing opposite to each other are shorter than the remaining four, 
which always stand in pairs. This inequality in their length 
determines them to be in the class Tetradynamia. The germ 
soon becomes a long pod called a silique, or a short thick one, 
called silicula ; this difference in the length of the two pods 
constitutes the distinction of the two orders of the class in which 
they are placed. 
The plants belonging to this class are herbaceous, the leaves 
alternate, the cabbage, the mustard, the radish, and stock-gilly- 
flower belong to this family. They are found on a chemical 
analysis to contain some sulphur. 
Class 14. 
Dicotyledons. Corolla polypetalous , stamens perigynous, 
(around the germ.) 
In this class we find the family rosacece, having rosaceous 
corollas, a calyx mostly uin-form ; petals usually 5, inserted in- 
to the top of the calyx ; stamens indefinite, generally over 10. 
The structure of the fruit varies in some; as in the apple, (Po- 
Class 13th — Dicotyledons — Corolla polypetalous — Stamens hypogynous 
— Cruciferie — Description of the family Cruciform — Class 14th — Dicotyle- 
dons — Corolla polypetalous — Stamens perigynous — Rosacea:. 
