Bridge and Haddon, op. cit. p. 234, Pl. II. Fig. 18.
Ibid. p. 216.
Weber, De aure et auditu Hominis et Animalium, Leipzig, 1820, p. 73.
Moreau, Compt. Rend. lxxx. 1875, p. 1247.
Coggi, Mitth. Zool. Stat. Neapel, vii. 1887, p. 381; Swale Vincent and Stanley Barnes, Journ. Anat. and Phys. xxx. 1896, p. 545.