[2] Cf. J. Graham Kerr, Proc. Camb. Phil. Soc. x. 227.

[3] For electric organs see W. Biedermann, Electro-Physiology.

[4] J. Graham Kerr, Quart. Journ. Micr. Sci. vol. xlvi.

[5] J. Graham Kerr, The Budgett Memorial Volume.

[6] J. Phelps, Science, vol. N.S. ix. p. 366; J. Eycleshymer and Wilson, Amer. Journ. Anat. v. (1906) p. 154.

[7] J. S. Budgett, Trans. Zool. Soc. Lond. xvi., 1901, p. 130.

[8] L. Drüner, Zool. Jahrbücher Anat. Band xix. (1904), S. 434.

[9] J. Graham Kerr, Quart. Journ. Micr. Sci. xlvi. 423.

[10] J. S. Budgett, op. cit.

[11] W. E. Agar, Anat. Anz., 1905, S. 298.