Are the Effects of Use and Disuse Inherited?

65

See pp. 179-182, Evolution and Disease, by J. Bland Sutton, to whom and to our mutual friend Dr. D. Thurston I am indebted for information on various points.

66

Variation of Animals and Plants under Domestication, ii. 290; i. 454.

67

Essays on Heredity, p. 104. Weismann's theory is clear, simple and convenient, but incomplete; for, unlike Darwin's theory of pangenesis, it scarcely attempts any real explanation of the extremely complex potentialities possessed by the reproductive elements. Perhaps we might retain Darwin's self-multiplying gemmules without supposing them to be thrown off by the cells, which will no longer be credited with two modes of multiplication. These minute germs or gemmules may have been evolved by natural selection playing upon the sample germs that achieve development; and they may exist either separately, or (preferably but perhaps not invariably) in aggregates to form Weismann's germ-plasm.

68

Contemporary Review, Dec., 1875, p. 88.

69

Variation of Animals and Plants under Domestication, ii. 286.

70

Variation of Animals and Plants under Domestication, ii. 388, 398, 367; Life and Letters, iii. 44.

71

Contemporary Review, Dec., 1875, pp. 94, 95.

72

Professor Romanes had casts made of the feet of upland geese, and could not detect any diminution as compared with the web of other geese in relation to the toes.