[57] “Über den morphol. Sitz der Hasenscharten Kieferspalten,” ‘Biolog. Central.,’ Bd. v, 13, pp. 80 and 122.
[58] “Lippen und deren Complicationen,” ‘Virchow’s Archiv,’ cxi, p. 138.
[59] Occasionally the lateral or accessory incisor may be developed or suppressed on one side only, a fact explaining the occasional occurrence of cases with three or five incisors present.
[60] Kölliker, op. cit., p. 369.
[61] Biondi, op. cit.
[62] ‘Langenbeck’s Archiv,’ xl, p. 795.
[63] ‘Trans. Med.-Chir. Soc.,’ 1845.
[64] Churchill, 3rd edition, 1881, chap. vi.
[65] Op. cit., p. 109.
[66] ‘Archiv f. klin. Chirurg.,’ v, p. 52.