viii Index . 
Figures. page 
n-14. Diagrammatic schemes to represent phyllotaxis ; the axis viewed as if split longi- 
tudinally and spread out flat (Saunders) . ....... 141 
15-23. 15. Reseda odorata, vegetative axis. 16. Flowering axis of the same. 17. Viola 
tricolor, showing contours of bract and sepal extensions. 18-20. Calystegia 
dahurica. 21. Epilobium parviflorum. 22, 23. Lupezia coronata, showing the 
leaf-extension edges flanked with a line of hairs (Saunders) . . . .142 
24. Diagram to illustrate the mode in which leaves are developed from the growing- 
point of a Phanerogam (Saunders) 145 
25. Ipomoea sanguinea, showing the appearance of the hypocotyl as seen in transverse 
section at successive levels from above downwards (Saunders) . .147 
26-29. 26. Lopezia coronata, stem in transverse section showing the contour lines of the leaf- 
extensions as eight ridges flanked with a line of hairs. 27. Calystegia dahurica, 
showing similar ridges without hairs. 28, 29. Antirrhinum Orontium, hypocotyl 
in transverse section showing an early and a later stage in the development of an 
exogenous adventitious bud (Saunders) . . . . . . . . 153 
30,31. 30. Lobelia fulgens. 31. Cytisus purgans (Saunders) . . . . . .154 
32,33- 32. Hedera Helix, seedling plant; a dicotyledon type with circular leaf-insertion. 
33. Tinantia fugax, a monocotyledon type with a conspicuous line of hairs along 
the line of fusion of the edges of the tubular sheath and of the leaf-extension 
(Saunders) 156 
34. Longitudinal section through the stem apex of Equisetum telmateia (Saunders) 159 
i,2, 1. Longitudinal section of thallus through the thickened median portion, showing 
hypha from a rhizoid branching, ramifying through the thallus, and bearing 
storage organs and chlamydospore. 2. Ditto through the thallus, showing an 
almost mature antheridium with fungal hyphae around it (Ridler) . . . 198 
3. Ditto through the thallus with archegonia, showing fungal hyphae in close proximity 
to them (Ridler) 199 
4, 5. 4. Ditto through the thallus in the region of the foot. 5. Ditto through the seta of 
an infected sporogonium (Ridler) 200 
6. Ditto through part of the seta and capsule of an infected sporogonium, showing 
hyphae passing from the seta into the capsule (Ridler) . . . . .201 
7. Ditto through part of the capsule of an infected sporangium, showing hyphae 
inside the young gametophytes, and a pycnidium produced on the wall (Ridler) 202 
8. Schematized drawing of a longitudinal section through the thallus and sporogonium 
(Ridler) ' 204 
1. The increase in weight of roots on cuttings of Tradescantia (Priestley and 
Evershed) 228 
2. The growth of roots on Tradescantia cuttings (dry weight) (Priestley and 
(Evershed) 230 
3. The production of roots on Tradescantia cuttings of initially different weights — 
5.0 and 2-5 grm. (Priestley and Evershed) 232 
4. ‘Dry weight ratio’ of roots on cuttings of ‘Sunrise’ tomato (Priestley and 
Evershed) 233 
5. The dry weight ratio for roots from cuttings of ‘Princess of Wales’ tomato 
(Priestley and Evershed) 234 
6. The data of Table I plotted as a rate-curve showing Sachs’s ‘ Grand Period ’ of 
growth (Priestley and Evershed) 236 
1. The growth curve for yeast (diagrammatic) (Priestley and Pearsall) . . 241 
2. Diagrammatic representation of the growth of yeast in a limited amount of nutrient 
solution (Priestley and Pearsall) - 242 
3. The increase in weight of- roots from cuttings (diagrammatic) (Priestley and 
Pearsall) 243 
4. The growth of pea roots at high temperature (35 0 C.) (Priestley and Pearsall) 246 
1-8. Studies on Intrafascicular Cambium in Monocotyledons (Arber) .... 253 
1. Growth of Botrytis cinerea on apple gelatine at 15 0 (Brown) .... 271 
2. Ditto at 5 0 (Brown) ............ 272 
