[11] Kerner, p. 12.

[12] Lubbock's "Wild Flowers in Relation to Insects," p. 56.

[13] Lindley, "Veg. King." 436.

[14] "Ueber die Bestaubungsvorrichtungen bei den Fumariaceen," in Pringsheim's "Jahrbuch," vol. vii. part iv. p. 423. 1870.

[15] Link, "Report on Progress of Botany during 1841," translated by Lankester (Ray Society, 1845), p. 65.

[16] Meehan, "On Fertilization by Insect Agency." Gardeners' Chronicle, 11 Sept. 1875.

[17] For the whole subject of these most curious flowers, see Mr. Darwin's book "On the Different Forms of Flowers;" Rev. G. Henslow, Tr. Linn. Society, "Botany," 2nd series, vol. i. p. 317; Mr. Bennett, Journal of Linn. Society, "Botany," xiii. p. 147, xvii. p. 269.

[18] Bennett, Journal of Linn. Society, "Botany," xiii. p. 147.

[19] Meehan, "On Fertilization," ubi supra.

[20] Mr. Bennett, "On Cleistogamous Flowers," Linn. Society's Journal, "Botany," xvii. p. 278, has shown that the latter is probably the correct view.