certain Orders of the Ranales . 68 1 
that stage in the phylogeny in which a bundle from the ventral side is in 
the act of uniting with a bundle of the dorsal arc ; in other orders, viz. 
Ranuncutaceae and Magnoliaceae, we see this process actually taking 
place in the ontogeny ; in Anonaceae and Paeoniaceae the process is no 
longer seen in actual operation, but certain stages of it have become fixed 
and arise congenitally as such in the individual life-history. Eupomatia 
represents the most advanced type of this order in which an ordinary 
arc of bundles extends throughout the leaf. The concentric bundles which 
occur in the leaf of this order are homologous with those which occur in the 
cortex of the stem of Magnoliaceae and Paeonia which is only another 
instance of the fact that a given structure which in one group of plants 
is found only in the leaf, may in another occupy that part of the stem which 
is a direct continuation of the leaf ; this supports my view of the origin of 
the cortical bundles of Calycanthaceae and also the phyton theory. 
In conclusion I must thank the authorities of the Royal Gardens, 
Kew, for valuable material supplied to me for this work. 
EXPLANATION OF FIGURES IN PLATES XXXII 
AND XXXIII 
Illustrating Mr. Worsdell’s paper on the Vascular System in the Ranales. 
Abbreviations used : — v. cb — ventral cortical bundle ; vb = ventral bundle ; cx — cortex ; 
mb — medullary bundles ; cc — central cylinder of stem ; ax. c = cylinder of axillary branch ; 
lb — leaf-base; cb = cortical bundle ; si. b — stipular bundles; hp = hollow pith; p = pith. 
All figures are diagrammatic, and represent transverse sections. 
Fig. i. Anemone rivularis, Buch.-Ham. ; flowering stem. 
Fig. 2. Anemone nemorosa, L. ; segment of central cylinder from bracteal node of flowering 
stem. 
Fig. 3. Anemone nemorosa, L. ; typical region of petiole. 
Fig. 4. Anemone apennina , L. ; typical region of petiole. 
Fig. 5. Anemone sylvestris, L. ; flowering stem. 
Fig. 6. Helleborus viridis , L. ; typical region of petiole. 
Fig. 7. Helleborus odorus, Waldst. and Kit. ; subdivision of lamina. 
Fig. 8. Thalictrum flav-um , L. ; typical region of petiole. 
Figs. 9, 10, 11. Thalictrum Jlavum, L. ; successive modifications in sheathing base of petiole 
in passing from above downwards. 
Fig. 12. Thalictrum flavum , L. ; segment of flowering stem. 
Fig. 13. Clematis V it alba, L. ; stem. 
Fig. 14. Clematis heracleifolia, DC.; typical region of petiole. 
Fig. 15. Clematis alpina, Mill ; typical region of petiole. 
Fig. 16. Caltka palustris, L. ; typical region of petiole. 
Fig. 17. Caltha palustris , L. ; lower region of petiole. 
Fig. 18. Caltha palustris , L. ; base of petiole after union with stem. 
Fig. 19. Paeonia , sp. (herbaceous type) ; typical region of petiole. 
