Anatomy of Flowering Plants(NCERT)
285741
The xylem fibres are classified into
1 protoxylem and metaxylem
2 primary and secondary fibres
3 fibre tracheids and fibres
4 long and short fibres
Explanation:
(c)Xylem fibres are of two types: libriform thick walled with simple pits and fibre tracheids thin walled with reduced bordered pits.