50 BOTANY. 
of one or more tissues; this reduction may be so great as 
to leave but a single tissue, which in many cases is com- 
posed of only a few spiral ves- 
sels or tracheids (Fig. 82). In 
other cases, instead of spiral 
vessels the bundle may consist 
of a few fibres of bast; or of 
elongated, thin-walled cells, 
which are doubtless to be re- 
garded as meristem-cells which 
failed to fully change into one 
of the ordinary permanent tis- 
sues: this last is a very com- 
mon accompaniment of reduced 
bundles. 
Practical Studies.—(a) Break a 
stem of the Indian corn and note 
with the naked eye the tough string- 
like fibro-vascular bundles which run 
through the soft tissues. Examine 
ere = in like manner the fibro-vascular 
vane, Be F Terminal portions of Abro’ bundles of the common door-yard 
to tracheids and spiral vessels. Plantain. 
(0) Make a very thin cross-section 
of the stem of Indian corn and, using the microscope, study the bun- 
dles carefully by comparing with Fig. 25. In bundles from young 
stems the fibrous tissue will not show as good a development as in 
the figure. : 
(c) Now make thin longitudinal sections of a bundle in such a man- 
ner as to have the sections pass through @ and 7 in the figure. This 
may be done by slicing the stem ina longitudinal radial direction. 
Study again by comparison with the figure and with the previous 
specimen. 
(ad) Make thin longitudinal sections of a bundle at right angles to 
the last (by longitudinal tangential sections of the stem). 
(e) Study in like manner the bundles of sugar-cane and asparagus. 
(f) Study by similar sections the bundles of the young stem of 
