Index. 
IX 
Figures. page 
1. Transverse section of a tetrasporic thallus of Rhoaymenia palmata, showing the 
scattered groups of tetraspores embedded in the tissue forming the outer cortex of 
the thallus (Grubb).151 
2. Outline drawings of transverse sections through procarpial thalli. a. Section 
through a group of young procarps, showing the trichogyne in various stages of 
development. B. Section through mature procarps, showing the chains of cells, 
and an elongated trichogyne with its nucleus (Grubb) ..... 152 
1. Conidiophore showing swollen vesicle, with whorl of 5 conidia, and a secondary 
vesicle, on which conidia are beginning to develop (Tabor and Bunting) . 154 
2. a, b, c. Oogonia from cells of mesocarp of cocoa pod, showing the numerous 
sacculae and amphigynous antheridia. D. Section of oogonium with ripe 
oospore. E. Oogonia with detached antheridia found in desiccated material 
three and a half months old (Tabor and Bunting).155 
3. Portion of mycelium from artificial culture showing conidia and oogonia (Tabor 
and Bunting).156 
i~ 3 - i* Fusion of the two cyst cells and neighbouring cells in the parenchymatous tissue 
of a perianth leaf of Anthurium Scherzerianum, third cell row from the epidermis. 
The two large cyst nuclei can be distinguished from one another. Formation of 
a crystal colony in one of the cysts. 2. The section following that of 1, 
showing the nuclei lying against the cell-wall. 3. Large cyst cell from the 
parenchymatous tissue of the perianth leaf of Anthurium Scherzerianum, demon¬ 
strating the large cyst nucleus after the fusion of a number of nuclei. Another 
nucleus of a neighbouring cell, united, and ready to fuse with the main nucleus. 
Fusion of the main symplast cell with other neighbouring cells. Many crystal 
colonies formed in different directions. Nuclei of the neighbouring cells lying 
more or less against the cell-wall. Some of these nuclei becoming homogeneous 
(Samuels) ..162 
4, 5. 4. Part of the tissue' of a perianth leaf of Anthurium Scherzerianum, third cell 
row from the epidermis. Fusion of a large cyst cell with a neighbouring cell. 
Fusion of the cyst nucleus with the nucleus of the latter. At the other end of the 
cyst another nucleus ready to unite with the large cyst nucleus. Nuclei of the 
neighbouring cells with a normal form showing a tendency of lying along the 
cell-wall. 5. Fusion of four cells to a large symplast in the parenchymatous 
tissue of the perianth leaf of Anthurium Scherzerianum. Union of the nuclei of 
the upper two cells. The nucleus of the third and a piece of that of the fourth cell 
can be seen at the other pole of the young cyst cell (Samuels) .... 163 
1. a-d. Transitions between scalariform and simple perforations in the vessels of 
Symphoricarpos occidentalis (Thompson) . . . . . . .184 
2, 3. 2. a, b. Reticulate perforations in Helianthus sp. 3. A. Reticulate perforation 
from Cordia myxa. B and c, from Cordia suaveolens (Thompson) . . *185 
4-7. 4. A. Vessel from Tecoma radicans. B and c, from Bougainvillea speciosa. 5. A-D. 
Scalariform-reticulate perforations from Tropaeolum. 6. Vessels from Cordia 
callacosa, a showing evidence of the loss of reticulations. 7. a-f. Stages in the 
disappearance of reticulate perforations in Potentilla monspeliensis (Thompson) 186 
8-11. a-f. Scalariform-reticulate perforations and their fusion in Cydonia. 9. A and B. 
Loss of reticulations in vessels of Tropaeolum. 10. a-c. Perforations in 
Epacris coriacea. 11. a and B. Perforations in E. coriacea (Thompson) . . 187 
1. Hollow curves exhibited by the grouping into sizes of the genera in the first fifteen 
largest families of flowering plants (Willis) ....... 204 
2, 3. 2. Logarithm curve for Rubiaceae (from Willis, ‘Dictionary’) with corresponding 
curve for all flowering plants beside it (from Willis, ‘ Age and Area ’). 3. Lo¬ 
garithm curve for Chrysomelid beetles, with corresponding curve for all flower¬ 
ing plants beside it (from Willis, ‘Age and Area’) (Willis) .... 205 
4. Hollow curves exhibited by the grouping into sizes of the genera in ten British 
Floras, 1782-1908 (Willis).208 
5. Map of the British Isles to show ranges of plants reaching co. Dublin (Willis) . 212 
