14 
ORGANOGRAPHY. 
BOOK I. 
each other; as, for example, is visible in the leaf of the white 
lily, and in the pulp of the strawberry or of other soft fruits, 
or in the dry berry of the Jujube. All other forms are con- 
sidered to be caused by the compression or extension of such 
spheroids. 
When a mass of spheroidal bladders is pressed together 
equally in all directions, rhomboidal dodecahedrons are pro- 
duced, which, if cut across, exhibit the appearance of hexa- 
gons. (Plate I. fig. 12.) This is the state in which the tissue 
is found in the pith of all plants; and the rice paper, sold in 
the shops for making artificial flowers, and for drawing upon, 
which is really the pith of a Chinese plant, is an excellent 
illustration of it. If the force of extension or compression 
be greater in one direction than another, a variety of forms 
is produced, of which the following are the most worth 
noticing : — 
1. The oh long ; in the stem of Orchis latifolia, and in the 
inside of many leaves. (Plate I. fig. 9.) 
2. The lohed (Plate I. fig. 2.y’) ; in the inside of the leaf 
of Nuphar luteum, Lilium candidum, Vicia Faba, &c. : in 
this form of cellular tissue the vesicles are sometimes oblong 
with a sort of leg or projecting lobe towards one end; and 
sometimes irregularly triangular, with the sides pressed in 
and the angles truncated. They are well represented in the 
plates of Adolphe Brongniart’s memoir upon the organization 
of leaves, in the Annates des Sciences^ vol. xxi. 
3. The square ; in the cuticle of some leaves, in the bark 
of many herbaceous plants, and frequently in pith. (Plate I. 
fig. 13.) 
4. lihe prismatical ; in some pith, in liber, and in the vici- 
nity of vessels of any sort. (Plate I. fig. 6.) 
5. The cylindrical (Plate I. fig. 8. a) ; in Chara ; this has 
been seen by Amici so large, that a single vesicle measured 
four inches in length and one third of a line in diameter. 
(Ann. des Sciences^ vol. ii. p, 246.) 
6. The fusiform or the oblong pointed at each end ; in the 
membrane that surrounds the seed of a Gourd. (Plate I. 
fig. 5.) 
7. The muriform ; in the medullary rays. This consists of 
