''234 Wigglesworth . — The young Sporophytes of Lycopodium. 
EXPLANATION OF PLATE XXII. 
Illustrating Miss Wigglesworth 1 s Paper on Lycopodhim. 
Figs, i and 2. L. complanatum. Young sporophytes. r 1 = first root, r 1 = second root,// = foot, 
pa = pseudo-adventitious bud, l l and Y 2 = first and second scale-leaves. Fig. 1 x 1, Fig. 2 x i|. 
Fig. 3. Z. complanatum. Transverse section through root showing two groups of xylem. 
en == protective sheath, /c = pericambium, px — protoxylem,//* = phloem, x 150. 
Fig. 4. Z. clavatum. Portion of a transverse section through the lower part of stem showing 
a diarch rootlet in the cortex, rt = rootlet, px = protoxylem, mx — metaxylem, ph — phloem, 
ep = epidermis of stem, x 164. 
Fig. 5. Z. complanatum. Transverse section through central region of rootlet showing two 
xylem groups fused, forming a crescent-shaped mass. Lettering as in Fig. 3. x 200. 
Figs. 6, 7, 8. Z. complanatum. Transverse sections through central region of rootlet showing 
branching. In Fig. 6 the xylem of smaller branch separates off from two groups of xylem which 
have previously fused to form a crescent-shaped mass ; in Fig. 7 it comes off from only one of the 
xylem groups ; Fig. 8 shows the xylems of the two branches completely separated. Lettering as in 
Fig. 3. x 200. 
Fig. 9. L. complanatum. Portion of transverse section through basal region of first root 
showing three groups of xylem. ep — epidermis, c = cortex, i.s. — intercellular space, pc = peri- 
cambium, en — protective sheath, px = protoxylem, ph = phloem, x 300. 
Fig. 10. Z. complanatum. Portion of transverse section through lower region of stem 
showing young rootlet, ep — epidermis of stem, i.s. — intercellular space, c = cortex, en = pro- 
tective sheath, x 109. 
Fig. 11. Z. clavatum. Transverse section through stem at a slightly higher level than that 
shown in Fig. 4 showing connexion of the rootlet stele with that of the stem, rt = rootlet, 
st = outer tissues of stem, x 90. 
Fig. 12. L. complanatum. Transverse section through foot region, p — remains of prothallus, 
en = protective sheath, t = tracheide. x 71. 
Fig. 13. Z. complanatum. Transverse section through central region of foot at a slightly 
higher level than that shown in Fig. 12. Lettering the same as in Fig. 12. x 150. 
Fig. 14. Z. complanatum. Transverse section through lower region of stem showing isolated 
central metaxylem and three groups of protoxylem at the periphery of the stele. A leaf is cut 
longitudinally and a portion of the leaf-trace is shown. It = leaf-trace, l — leaf, pc = pericambium,, 
en — protective sheath, ic = inner cortex, me = middle cortex, ep = epidermis, x 82. 
Fig. 15. Z. complanatum. Transverse section through stem and pseudo-adventitious bud {pa in 
Fig. 2) showing main branch of stem (a) and retarded branch (b) which has produced a root (rt),. 
I = leaf, x 71. 
Fig. 16. Z. complanatum. Xylem elements of stem in longitudinal section. 
Fig. 17 a, b , c. L. complanatum . Successive transverse sections through the peripheral 
portion of one of the xylem rays and the surrounding tissues in the upper part of the stem showing 
outgoing leaf-trace, the dotted cells represent the curiously thickened tracheides of the leaf-trace. In 
17 c, where the leaf-trace tracheides have become separated from the main xylem mass, they are 
surrounded by cells with large nuclei which apparently represent phloem, en — protective sheath, 
It = leaf-trace, ph — phloem, px = protoxylem. x 147. 
Fig. 18. Z. complanatum . Part of a longitudinal section through a leaf on the upper part of 
the stem showing thick-walled phloem, ep epidermis, m = mesophyll, i.s. — intercellular space. 
t = tracheide, ph = phloem, x 247. 
Fig. 19. Z. complanahim. Transverse section through the central tissues of leaf from upper 
ipart of the stem. The vascular bundle is represented by thick-walled cells, the outer ones of which 
contain protoplasm and represent phloem (ph). x 187. 
Fig. 20. Phylloglossum Drummondi. Transverse section through stele of a root, en ' — endo- 
dermis,/w — protoxylem, /Z = phloem. 
Fig. 21. Lycopodium Hippuris. Sieve-tubes in longitudinal section, x 600. 
