[DQ]Ibid. p. 56.
[DR]Nature, vol. xxxvi. p. 592.
[DS]Quoted from "Medical Notes and Reflections," 1855, p. 267, by Darwin, "Animals and Plants under Domestication," vol. i. p. 446.
[DT]Darwin, "Animals and Plants under Domestication," vol. i. p. 465.
[DU]"Natural Inheritance," p. 12.
[DV]Darwin, "Animals and Plants under Domestication," vol. ii. p. 70.
[DW]"Organic Evolution," Mr. Cunningham's translation, p. 76.
[DX]Darwin, "Animals and Plants under Domestication," vol. i. p. 104.
[DY]Similarly, from a chance sport of a one-eared rabbit, Anderson formed a breed which steadily produced one-eared rabbits ("Animals and Plants under Domestication," vol. i. p. 456). This is an example of asymmetrical variation. Variations are generally, but not always, symmetrical. Superficial colour-variations are sometimes asymmetrical. Gasteropod molluscs are nearly always asymmetrically developed. Among insects, Anisognathus affords an example of the asymmetrical development of the mandible. Our right-handedness is a mark of asymmetry.
[DZ]"Natural Inheritance," p. 32.