466 Harvey -Gibson. — Anatomy of Selaginella . 
PLATE XXL 
Fig. 21. Root-system of S’. Lyallii, Spr. Nat. size. 
Fig. 22. Forking of the root-stele in S. Lyallii. x 350. 
Fig. 23. Root-system of S. Kraussiana , A. Br. Nat. size. 
Fig. 24. Successive sections showing the mode of origin of the steles of the 
lateral branch and root in S. canaliculate 1, Baker. Diagr. 
Fig. 25. Transverse section of the root of S. Willdenoivii, Baker, showing 
the almost isolated protoxylem. x 350. 
Fig. 26. Successive sections of the stem of S. Willdenowii, Baker, showing the 
mode of origin of the vascular systems of the root and lateral branch. Diagr. 
