[422]

The mechanism is apparently absent in one species of Pangasius (P. micronema). Bridge and Haddon, op. cit. p. 220.

[423]

Moreau, Compt. Rendus, lix. 1864, p. 436; Ann. d. Sci. Nat. (6) iv. 1876, p. 65.

[424]

Sörensen, Lydorganer, p. 82, et. seq.

[425]

Cf. Mettenheimer, Arch. f. Anat. u. Physiol. 1858, p. 302.

[426]

Günther, Phil. Trans. 161, 1871, p. 542.