26 BOTANY. 
Practical Studies,—The student should here make a good many 
observations upon the tissues described above, so as to become thor 
oughly familiar with at least their typical forms. The following out- 
line may direct him in his first studies: 
I. Soft Lissue.—(a) Make very thin cross and longitudinal sections 
of agreen stem of Indiancorn. After excluding the woody bundles, 
the whole of the central part of the stem is soft tissue. 
(6) Make similar sections of the central part of the stem of the cul- 
tivated geranium. 
(c) Make a very thin cross-section of an apple-leaf: the green 
cells are of soft tissue. 
(@ Mount a whole moss-leaf: it is entirely composed of soft tissue, 
although in its rudimentary midrib the cells have elongated, as if 
foreshadowing the higher tissues. 
(¢) Mount several threads of Pond Scum: the whole plant is here 
composed of soft tissue. 
IL. Thick-angled Tissue.—(a) Examine a leaf-stalk of the squash or 
pumpkin, and note the whitish bands, one or two millimetres wide, 
which extend from end toend just beneath the epidermis. These are 
bands of thick-angled tissue. They may be readily torn out, when 
the stalk will be found to have lost much of its strength. 
(6) Make a very thin cross section of the preceding leaf-stalk, and 
note the appearance of the thick angled tissue first under a low power 
and then under a higher. The sections must be made exactly at 
right angles to the axis of the bands of tissue in order to show well. 
(©) Make a number of longitudinal sections of the same leaf-stalk, 
in each case cutting through a band of the thick-angled tissue. Some 
of these will show the thickened angles, although there is always some 
difficulty in making them out in this section. 
(d) The stems of squash, pumpkin, Pigweed or Lamb's Quarters 
(Chenopodium), beet, and many other plants may be taken up next, 
and their thick-angled tissue studied in cross and longitudinal sec- 
tions. 
III. Stony Tissue.—(a) Break the shell of a hickory-nut, and after 
smoothing the broken surface cut off a very small thin slice; mount 
in water and a little potassic hydrate: the cell walls are so greatly 
thickened as to almost obliterate the cell-cavity. 
(6) Study similarly the stony tissue of the cocoa-nut, walnut, peach, 
cherry, etc. 
(c) Make cross-sections of the seed-coat of the apple, squash, melot 
wild cucumber (Echinocystis), etc. It is instructive to make sections, 
also, parallel to the surface of the seeds. 
(d) Make longitudinal sections of the pith of apple-twigs and note 
