Bischoff, Lepidosiren paradoxa, Leipzig, 1840; Hyrtl, Abhand. d. böhm. Gesellsch. 1845, p. 637; also Bridge, op. cit. pp. 344, 345.
Turner, Journ. Anat. and Phys. xiv. 1879, p. 273. For references to other writers see Turner, op. cit.
For this information, which was based on an examination of a specimen, parts of which are now in the Cambridge University Museum, I am indebted to Dr. Harmer.
Van Beneden, quoted by Turner, op. cit. p. 282.
Andrew Smith, also quoted by Turner, op. cit. p. 281.