VASCULAR TEXTURE. 
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The cellular texture composes most of the pith, parenchyma 
and cotyledons of almost all vegetables. It is abundant in tuber- 
ous roots, pulpy and fleshy fruits, and the stems of grasses, and 
constitutes the principal parts of mushrooms and other crypto- 
gamous plants. In the bark of plants, the cellular texture is sit- 
uated under the cuticle; it is filled with a juice which varies in 
colour in different species of plants, but is most commonly green ; 
it gives its colour to the bark, as the same texture under the hu- 
man cuticle gives colour to the skin. The green colour of leaves 
is caused py the cellular texture, which is inclosed on both sides 
by the cuticle. In the pith of young plants the cells are filled 
with watery fluids, but in older plants they are empty or only 
filled by air. 
The petals of flowers owe their beautiful hues to the presence 
of cellular texture, filled with juices, w r hich refract and reflect 
the rays of light. 
Vascular* texture , consists of tubes which like the vessels of 
the animal frame are capable of transmitting fluids. These tubes 
are open at both ends, and are protected by a thick coating of 
cellular integument ; their sides are thick and little transparent. 
These vessels extend throughout the whole plant, distributing 
air and other fluids necessary to vegetation. The vascular sys- 
tem of plants presents a variety as to form and with respect to 
the functions which the different vessels perform ; some are cal- 
led Moniliform , resembling in external appearance a string of 
beads ; these serve to connect larger vessels, and to convey sap 
from one set to the other. Some are entire vessels, or without 
any perforation ; these convey the proper juices of the plant and 
are generally found containing oils and resinous juices. Porous 
vessels have their sides pierced with many perforations ; they 
are not continuous tubes, but often separate and again unite, 
changing at length into cellular integument. Spiral vessels are 
so called from their form, resembling that of a screw ; they are 
sometimes termed trachea from a supposed analogy to the tra- 
chea, or the organs of insects for breathing. These vessels are 
formed of a thread like fibre turned spirally from right to left. 
Mosses, fungi, and lichens have no vascular system ; but their 
vessels are all of the cellular kind. The fibres of plants are all 
composed of some varieties of the two kinds of vessels we have 
now described. Roots and stems are composed of fibres ; these 
may easily be split longitudinally, as the vessels in this case are 
only separated, and the cellular texture easily yields : but in cut- 
*Tho term vascular is derived from the Latin word vasculum, a little 
vessel. 
Cause of the green colour of plants — Beautiful hues of petals — Vascular 
texture — Its variety of forms — Cellular integument. 
