[92] To V. Carus, November 21, 1866.
[93] To D. Mackintosh, February 28, 1882.
[94] Riddle of the Universe, p. 6.
[95] As regards Protoplasm, p. 21.
[96] Encyclopaedia Britannica, "Biology."
[97] Printed in Lay Sermons.
[98] Nature, June 5, 1902, p. 121.
[99] Id. ibid.
[100] Op. cit. p. 27.
[101] Presidential Address, British Association, 1887.