of the Anatomy of the Genus Selaginelia, Spr, 205 
Fig. 63. S. canaliculata , Bak. 
Lacunar tissue and endodermal cells ( x 350). 
Figs. 64-65. S. Mettenii , A, Br. 
Fig. 64. Mode of fusion of the steles at the origin of a branch. 
Fig. 65. Transverse section of the dorsal stele. Letters as in Fig. 59. 
Fig. 66. S. Lohbii , Moore. 
I-IV illustrate the gradual fusion of the steles in the procumbent axis from 
the erect axis backwards. IV a shows the partially sunk protoxylem at the comers 
of such a stele as that represented in IV. 
Figs. 67-70. S . inaequalifolia , Spr. 
Fig. 67. I-V. Serial sections illustrating the transition from the monostelic to 
the tristelic condition in the creeping axis. 
Fig. 68. Transverse section of a small portion of the stele from the monostelic 
axis (xBoo). a, metaxylem ; b, protoxylem; c, phloem parenchyma; d, sieve- 
tubes ; e, pericycle ; f } cuticle on the outer layer of the pericycle ; g, inner cortex ; 
h, silica. 
Figs. 69-70. Cuticularized cells joining the primary and accessory steles. 
Figs. 71-72. S. viridangula, Spr. 
Fig. 71. Scheme of the mode of union of the steles at the branchings. 
Fig. 72. Fragmentation of the ventral stele (x 350). 
Fig. 7 3. S. chilensis, Spr. 
Scheme of the mode of union of the leaf-traces and arrangement of pro- 
toxylem s. 
Fig. 74. S. Lobbii, Moore. 
Transverse section of part of the stele ( x 550). 
Fig. 75. S. canaliculata, Bak. 
Transverse section of the margin of the stele (550). 
Fig 76. S. laevigata , Bak. var. Lyallii , Spr. 
Transverse section of the stele and inner cortex of the rhizome, a, outer 
cortex ; b, inner cortex ; c, cuticularized endodermal cells ; d, pericycle ; e, sieve- 
tubes ; f phloem-parenchyma ; g, metaxylem ; h, protoxylem ; i, phloem-paren- 
chyma ; k, sieve-tubes ; l, pericycle ; m, cuticularized endodermal cells; n, pericycle ; 
0, sieve-tubes ; /, phloem-parenchyma ; r, metaxylem ( x 350). 
PLATE XII. 
Figs. 77-94. A. laevigata , Bak. var. Lyallii , Spr. 
Fig. 77. Side view of the rhizome, erect shoots and roots (nat. size). 
Fig- 7 ^- Scheme of the arrangement of steles in a terminal branch. Each of the 
small circles encloses one distinct stele. 
Fig. 79. End view of rhizome, &c. (nat. size). 
Fig. 80. Fibres of outer cortex in transverse section showing middle lamella 
(X550). 
Fig. 81. Transverse section of one of the primary steles. 
Fig. 82. Steles of the rhizome and of the erect axis dissected out. 
