[174] Pidgeon, Nature, xxxix. p. 127.
[175] W. Anderson Smith, Loch Creran, p. 46.
[176] Smart, Journal of Conch. v. p. 152.
[177] Animal Life, p. 351.
[178] Journ. of Conch. vi. 1891, p. 399.
[179] Ann. Mag. N. H. (6) vii. p. 276.
[180] Stimpson, quoted by Jeffrey’s Brit. Conch. ii. 194.
[181] Stimpson, Journ. Bost. Soc. N. H. vi. 1857, p. 48.
[182] E. H. Matthews, Conchologist, ii. p. 144.
[183] Thus Limnaea involuta, which is almost universally regarded as a good and distinct species, has been held to be no more than a variety of L. peregra produced by locality; see Zoologist, 1889, p. 154.