[139] For a popular sketch of these, see Sir J. Lubbock's Flowers, Fruits, and Leaves, or any general botanical work.

[140] Nature, vol. xv. p, 117.

[141] Grant Allen's Colour Sense, p. 113.

[142] Canon Tristram's Natural History of the Bible, pp. 483, 484.

[143] For a complete historical account of this subject with full references to all the works upon it, see the Introduction to Hermann Müller's Fertilisation of Flowers, translated by D'Arcy W. Thompson.

[144] For the full detail of his experiments, see Cross-and Self-Fertilisation of Plants, 1876.

[145] See Darwin's Fertilisation of Orchids for the many extraordinary and complex arrangements in these plants.

[146] The English reader may consult Sir John Lubbock's British Wild Flowers in Relation to Insects, and H. Müller's great and original work, The Fertilisation of Flowers.

[147] Müller's Fertilisation of Flowers, p. 248.

[148] "Alpenblumen," by D.H. Müller. See Nature, vol. xxiii. p. 333.