Vascular System of Matonia pectinaia . 
5*9 
PLATE XXXII. 
Fig. 15. Transverse section of proximal end of rhizome of plant D, showing central phloem 
enclosing a detached xylem strand and scattered endodermal cells uniting to form a crescentic strand. 
Sieve-tubes showing typical granules, x 160 (p. 485). 
Fig. 16. Transverse section of stele of proximal end of rhizome of plant E, showing a solenostele 
with local internal dilatation of xylem. x 130 (p. 486). 
Fig. 17. Transverse section through leaf-gap of fifth node of E. Internal xylem-strand free. 
X 100 (p. 486). 
Fig. 18. Next section but one; closure of gap; internal xylem-strand connected with outer 
xylem. x 100. 
Fig. 19. Five sections further on ; tracheids running obliquely from central strand to close xylem- 
gap. x 150 (p. 487). 
Fig. 20. Transverse section through fifth internode of E, showing internal strand separated 
from outer cylinder dorsally by endodermis, ventrally also by pith ; px? probably protoxylem of leaf- 
trace continued down into stele, x 120 (p. 487). 
Fig. 21. Transverse section of the beginning of the tenth node of E, showing tracheids from the 
internal strand running up into the leaf-trace, and phloem-elements in the interior of the internal 
strand, x 130 (p. 487). 
Fig. 22. Transverse section of the eleventh leaf-trace of E, near its base; sieve-tubes mainly 
round the convexity of the trace; ph.f ? probably fibres developed in phloem of concavity of leaf- 
trace ; px ? probably protoxylem ; int . end. internal endodermis. x 500 (pp. 488, 504). 
Fig. 23. Transverse section of a leaf-trace of G, near its base, showing the initiation of lateral 
loops by thickening of the free edge of the trace (left) and xylem-hook formation (right), px ? 
probably protoxylems. In the phloem covering the sides of the trace the sieve-tubes are normal ; 
round the middle of the convexity, thick-walled ; in the concavity of the trace and in the loop of the 
xylem-hook on the right, fibres are developed instead of sieve-tubes, x 350 (pp. 491, 504). 
Fig. 24. Diagram of transverse section of tricyclic stem in front of node, just before closure of 
gap in second cylinder, x 8. 
Fig. 25. Connexion of third cylinder with edge of gap in second, effecting closure, x 8. 
Fig. 26. Gap closed ; detachment of third cylinder from second, x 8. 
PLATE XXXIII. 
Drawings of wax models of the stelar system. 
Fig. 27. Side view of eighth node of F. x 25. 
Fig. 28. Front view of eighth and ninth nodes of F, showing connexion of second cylinder with 
outer one in front of insertion of ninth trace, x 40. 
Fig. 29. Segment of vascular system of rhizome and base of leaf-trace including front part of 
node, in simple dicyclic type, showing branching column of tissue rising from second cylinder to 
supply the lateral loops of the trace and close the gap in the first cylinder. Seen from behind, x 12. 
Fig. 30. Segment of vascular system of rhizome and base of leaf-trace including front part 
of node in most advanced tricyclic adult type, from behind, a. Roof of second cylinder rising to fill 
gap in first and coming into connexion with lateral loops of leaf-trace which bulge back freely above 
connexion ; 6. these backward bulges ; c. free edge of forwardly directed limb of lateral loop ; d. down- 
ward and forward continuation of c, forming flange on edge of gap in second cylinder, x 10. 
Fig. 31. The same from in front ; same lettering, x 10. 
