CALYX. 
85 
and in some few cases it is the most showy part ; as in the la- 
dy’s-ear-drop, where it is of a bright scarlet color, and the Egyp- 
tian Lily, where it is pure white. 
The calyx seems of use in protecting the other parts of the 
flower, before they expand ; and afterwards supporting them, 
by keeping all in their proper position. 
Pinks having petals with long and slender feet, which would 
drop or break without support, have a calyx. Tulips having 
firm petals, and each one resting upon a broad strong basis, are 
able to support themselves, and they have no calyx. 
In some plants the calyx serves as a seed-vessel ;■ as in the or- 
der Gymnospermia, of the class Didynamia, where there are four 
naked seeds lying in the bottom of the calyx. 
LECTURE XII. 
Corolla. 
The term corolla , or corol is derived from the Latin corona, 
a crown or chaplet. As the calyx is formed by a continuation 
of the fibres of the outer bark, the corolla is a continuation of 
the cellular integument, or inner coat of the same. The texture 
of the corolla is delicate, soft, watery, and colored. It exhales 
carbonic acid gas, but does not give off oxygen, either in the 
dark, or when acted upon by light ; as is the case with the 
green parts of plants. The cuticle or outward covering of the 
corolla is of an extremely fine texture. The rich and variegated 
colours of flowers, are owing to the delicate organization of the 
corolla ; and to this cause, its transient duration may also be 
attributed. 
The corolla exhibits every variety of color, except black ; flor- 
ists sometimes present us, with what they term, black roses, and 
we see some other flowers, which approach this color, yet none 
are perfectly black ; but the darkest may be considered, as a 
very deep shade of purple. 
Corollas are usually white, yellow, blue, violet, &c ; A 1 some, 
different colors are delicately shaded, and blended ; in others, 
they meet abruptly, without any intermediate tint. 
The color of the corolla, in the same species, often varies 
without any assignable cause : This fact is strikingly illustra- 
ted in the Four o'clock, (Mirabilis,) the flowers of which are 
Not an essential organ. 
Corolla — derivation of the term — a continuation of the cellular integu- 
ment — description of the corolla— colour. 
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