XU CONTENTS. 



PART IV.— Growth. 



Lecture XXVI.— The Distribution of the Phases of Growth in Space and Time . 411 

 The Growth of Plants compared with that of Crystals.— The Three Phases of 

 Growth. — Embryonic Conditions of Organs. — Elongation of Organs. — The Com- 

 pletion of Internal Differention in Organs. — Distribution of Growth in Non-Cellular 

 Plants. — Growth of Fungi. — Growth of Algae and Myxomycetes. 



Lecture XXVII.— Relations between Growth and Cell-division in the Embryonic 



Tissues 431 



Dependence of Divisions on the Form of the Mother-cell. — The Arrangement of 

 Cells Independent of the Morphological and Physiological Nature of the Organ. — 

 Net-works of Cell- walls. — Periclines, Anticlines, Trajectories. — Arrangement of Cells 

 in an Elliptical Disc. — Examples agreeing with the Diagram. — Sequence of Anti- 

 clines and Periclines immaterial. — Displacement of Division-walls by Growth. — 

 Anticlines and Periclines in an Ellipsoidal body. — Anticlines and Periclines in 

 Growing-points. — The Apex of the Growing-point grows most slowly. — Confocal 

 and Co-axial Arrangement of Cells. — Apical Cells. — Transverse Segments of Apical 

 Cells. — Tetrahedial Apical Cells. — Significance of the Apical Cell. 



Lecture XXVIII. — Formation of Organs at the Growing-point. Branching . 460 

 Forms of Growing-points. — Depressed Growing-points. — Metamorphosis of Growing- 

 point into an Organ. — Progressive Development of Organs at the Growing-point. — 

 Development of Leaves. — Development of Intemodes. — Shoots with and without 

 'Branches. — Dichotomy or Bifurcation. — Apparently Endogenous Inception of Shoots. 

 Adventitious Growing-points. 



Lecture XXIX. — Axis of Growth. Polarity. Laterality. Relations of Position 481 

 Axis of Growth, — Polarity in the Growing Axis. — Radial, Bilateral, Dorsi- ventral. — 

 Extension of the idea of Radial Structure. — Dorsi-ventral, Bilateral. — Dorsi- 

 ventrality. — Dorsi-ventral Shoots. — Laterality and Phyllotaxis. — Rejection of the 

 Spiral-theory. — Parastichies. — Divergences. 



Lecture XXX. — Causal Relations of Growth of the different Organs of the Plant 



one to another (Correlations) 502 



Conception of the Form of Plants. — Influence of Growing Shoots on other Shoots. — 

 Bud-scales are suppressed Foliage-leaves. — Organs of like kind as Competitors 

 for the same Formative Substances. — Assimilatory Tissue forms thin Lamellse. — 

 Assimilating Surfaces influence the Formation of Wood and Roots. — The Activity 

 of the Roots affects the Functions of Leaves. 



Lecture XXXI. — Influences of the Environment on the Processes of Configura- 

 tion in the Plant 



Inherited Disposition and External Influences. — Influence of Gravitation on the 

 Origin of Growing-points. — Influence of Gravitation on the Orientation of Growing- 

 points. — Movement of Shoot-forming and Root-forming Substances. — Development 

 of Roots on the side turned away from Light. — Dorsiventral Structure induced by 



Illumination. — Influence of Light and Gravitation on Post-embryonic Growth. 



Influence of Gravitation on Post-embryonic Growth. — Influence of Light on Post- 

 embryonic Growth. — Etiolation. — Flower-forming Reserve Substance in Bulbs, 



Tubers, &c.— Influence of Light on Post-embryonic Growth.— Gall-formations. 



Fertilisation. 



Lecture XXXII. — The Course of Growth during Elongation. Periodic Varia- 

 tions 



The Grand Period of Grovrth. — Distribution of Growth in the Growing Region. 



Length of the Growing Region.— Passive Motion of the Apices of Buds and Roots. 

 —Nutations due to Unequal Growth. Torsions due to Growth.— Growth by Day 

 and by Night.— Auxanometer.— Daily periods of Growth.— Daily periods in con- 

 tinued darkness. — Apparatus for Auxanometrical observation. 



515 



539 



