GROUPS OF TISSUKS, OR TISSUK-SYSTEMS. 51 
the Castor-oil Plant and Red Clover. The latter is very convenient 
for study, as the uppermost joints will furnish as young bundles as 
are required, while lower down all older stages may be obtained. In 
these note the cambium-zone. 
(g) Make very thin cross-sections of a root of germinating Indian 
corn. The first section should be made within a few millimetres of 
the root-tip. Others should then be made at a greater distance. By 
staining the specimens with carmine the sieve-regions may be demon- 
strated better, Note the bundle-sheath ; 
(A) Study in like manner the bundle in the stem of the Club-mosses 
(some of the species are known as Ground-pines), and if possible make 
comparison with sections of the smaller Club-mosses (grown in green- 
houses often under the name of Lycopodium, although they are in 
reality species of Selaginella). 
(@) Dig up the underground stem of the common Brake-fern 
(Pteris); preserve what is not wanted immediately in alcohol. The 
bundles may be seen by the naked eye by making a clean cross-cut 
and examining carefully in the region immediately surrounding the 
two dark masses of fibrous tissue. Make thin cross-sections and study 
with the microscope, comparing with Fig. 31. Longitudinal sections 
in two planes should be made as in ¢ and d above. 
(j) Make very thin longitudinal sections of some of the reduced 
bundles which constitute veins and veinlets of leaves, e.g., in gera- 
nium and primrose. 
(&) Make similar sections of the bundles of petals, e.g., fuchsia. 
() Soak petals of fuchsia for several days in potassic hydrate, then 
wash in water and carefully mount in pure water. The reduced 
bundles may generally be well seen by this treatment, 
94. The Fundamental System of Tissues.—This system 
includes all the tissues which in any part of a plant fre- 
quently make up the bulk of that part, but are not included 
in the epidermal or fibro-vascular systems. Thus if from 
any stem, for example, we should strip off the epidermis 
and then pull out the fibro-vascular bundles, that which 
remained would be the Fundamental System of Tissues. In 
those plants (of the lower orders) which have no fibro- 
vascular bundles everything inside of the epidermis belongs 
to the fundamental system. On the other hand, in the 
