[12] See also Browne, Lady Isabel (09) p. 4.
[13] Williamson and Scott (94) A. p. 911.
[14] Thoday (06).
[15] Scott (97) A.; see also Scott (00) p. 106.
[16] The term metaxylem may be conveniently applied to the primary xylem other than protoxylem; the latter is usually but by no means invariably characterised by spiral thickening bands.
[17] Scott (05) p. 21 (footnote).
[18] Vol. I. p. 354, fig. 95, C.
[19] Williamson (72) Pl. XLIV. p. 297, figs. 29, 30.
[20] ‘Exarch’ denotes that the protoxylem is on the outside of the primary xylem; ‘endarch’ that it is on the inner edge or in a central position; ‘mesarch’ that it is internal, either near the inner or the outer edge of the metaxylem.
[21] Nathorst (02) p. 24.