CALYPTRA. 
thus is noticed in the article Auuspicy (Caro- 
LINA). 
CALYPTRA. A membranaceous veil which 
masks the urn-shaped capsule of the moss-plants. 
It is a fine integument, and has the shape of a 
hollow cone. 
CALYPTRANTHES. A genus of ornamental, 
evergreen, tropical trees of the myrtle tribe. 
The clove-leaved species, C. caryophyllifolia— 
called by Decandolle Syzygium caryophyllefolium 
—is a native of India, and was introduced to the 
hothouses of Britain in 1822. It usually grows to 
the height of about twenty feet. Its flowers are 
white. Its fruit, when ripe, is of a very dark 
purple colour, and about the size of a large 
cherry ; and it tastes somewhat like the sloe, but 
is much sweeter. Its timber is used by the Hin- 
doos for making cots, carriage-frames, doors, 
windows, rafters, and handles of instruments, 
Its bark is astringent, and is used in decoction, 
by the Hindoo practitioners, as a remedy for dy- 
sentery, and as a wash for foul ulcers.—The zu- 
zygium species, 0. zuzygium, is a native of the 
West Indies, and is also used as a timber tree; 
and it was introduced to Britain about the mid- 
dle of the latter half of last century. Its specific 
name means “yoked together,” and alludes to 
the paired growth or yoking together of its 
leaves and branches.—The Jambolana species, 
©. Jambolana, is a native of the Indian archi- 
pelago, and is sometimes called the Java plum- 
tree. It was introduced to Britain about the 
close of last century.—All these three species, 
and also another, C. chytraculia, which was 
brought from the West Indies at the same time 
as the Zuzygium, carry white flowers, attain a 
height of about twenty feet, and are employed 
for various useful purposes.—Five or six other 
species have been described. 
CALYSTEGIA,—popularly Bearbind. A genus 
of hardy, twining, perennial plants, of the con- 
volvulus tribe, and partly included, till of late, 
in the convolvulus genus. See BrInpwEED. 
CALYTHRIX. A genus of ornamental, ever- 
green, Australian shrubs, of the myrtle tribe. 
Four species, the smooth, the abundant-flower- 
ing, the pubescent, and the heath-like, were in- 
troduced to Britain during the six years preced- 
ing 1825; and all these produce white flowers; 
the last is about two feet high, and each of the 
other three is about four feet high. The name 
Calythrix means “a triple calyx.” | 
CALYX. The exterior whorl or envelope of a 
flower. It is totally awanting in many flowers, 
as in the hyacinth; it constitutes the whole of 
the phyllous or leafy portion of many flowers, as 
in the Carolina allspice; and it forms a conspicu- 
ous portion of the brilliant or tinted portion of 
some flowers, as in the fuschia. It is thick and 
fleshy in many plants, as in the rose; and thin. 
and membranaceous in some, as in the common 
bindweed. It has, in many plants, as in the 
cereal grasses, the form of a glume; in others, as 
CAMBIUM. 657 
in the cones of the fir and the catkins of the 
willow, it has the form of a scale; but, in most 
calyciferous plants, it has the form of a flower- 
cup or whorled envelope; and when, as in most 
instances, it consists of more phyllous pieces than 
one, these pieces are technically called sepals, and 
correspond in general form and adjustment to the 
petals of the corolla. When, as in the poppy, a 
calyx falls before the other parts of the flower, it 
is said to be caducous; when, as in the lime- 
tree, it falls along with the other parts of the 
flower, it is said to be deciduous; and when, as 
in hypericum, it does not fall till after the other 
parts of the flower, it is said to be persistent. 
CAMBIUM. The elaborated sap of plants. 
The moisture imbibed by the roots and carried 
up to the leaves—receiving in its progress such 
soluble ingredients as it finds in its passage—is 
properly called the sap; and when this has been 
thoroughly elaborated in the leaf—by the evapo- 
ration of its superfluous hydrogen and oxygen, 
and by the fixation of carbon, and sometimes of 
ammonia—it becomes aliment for the plant, takes 
the name of cambium, and begins to descend 
from the leaf toward the root, or in the opposite 
direction to the ascent of the sap. The cambium 
is a limpid, viscous, mucilaginous fluid, of very 
compound chemical character, fitted to repair or 
augment such parts of the plant as are already 
formed, and to form such others as remain to be 
added ; and, in the course of its descent, it visits 
every portion of every member of the plant, 
making deposits wherever they are required, and 
gradually diminishing in its own bulk till, at the 
lower extremity of the plant, it becomes wholly 
expended. While the ascent of the sap is free, 
the descent of the cambium is fixational; and 
while the former may be compared to the mere 
chyle of animals, the latter may be compared to 
their blood. The grand deposits or assimilations 
of cambium in all exogenous plants, consist of a 
new concentric layer of woody matter exterior to 
the preceding year’s alburnum, and a new con- 
centric layer of cortical matter interior to the 
preceding year’s formation of liber; and hence, 
in the season of the plant’s growth, or after the 
commencement of the vernal copious ascent of 
sap, the descent of the cambium is found in full 
flow between the wood and the bark. 
As the same tide of blood simultaneously sup- 
plies bony matter to bone, muscular matter to 
muscle, cartilaginous matter to cartilage, corne- 
ous matter to horn, and hairy matter to hair; so 
the same stream of cambium supplies alburnous 
matter to wood, cortical matter to bark, phyllous 
matter to buds and leaves, and fructiferous matter 
to flowers and seeds. Though the descent and 
functions of the cambium are incomparably less 
obvious in endogens than in exogens; yet both 
their reality and their mode of action may be 
quite certainly and very clearly inferred from 
identity between the two great classes of plants, 
in the general forms and principles of vegetable 
* = os 
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