1. See Arber and Parkin, Proc. Linn. Soc. Bot., vol. xxxviii., p. 29, 1907, and Annals of Bot., vol. xxii., p. 489, 1908
2. See NATURE, vol. lxxi., p. 68, 1904; and p. 426, 1905; vol. lxxv., p. 329, 1907; vol lxxvi., p. 113. 1907.
3. Kidston and Gwynne-Vaughan, Trans. Roy. Soc., Edinburgh, vol. xlv., p. 759, 1907; vol. xlvi., pp. 213. 651, 1908–9.
4. Gwynne-Vaughan and Kidston, Proc. Roy. Soc., Edinburgh, vol. xxviii., p. 433, 1908.
5. Kidston, Trans. Roy. Soc. Edinburgh, vol. xli., p. 533, 1905; Proc. Roy. Soc. Edinburgh, vol. xxvii., p. 207, 1907.