Rachilla a secondary axis in the inflorescence of the grasses, the axis of the spikelet, 13. Rachis axis of an inflorescence, 13. Retuse with a shallow notch at the apex, 67. Rhizome root-stock or under ground stem prostrate on the ground, 5. Rugulose somewhat wrinkled, 90. S Scaberulous slightly rough due to the presence of short hairs, 69. Scabrid somewhat rough, 75. Scale a reduced leaf, 10. Sclerenchyma elongated cells with pointed ends and much thickened cell-wall. Scutellum the single cotyledon found in connexion with the embryo in grass grains, 18. Secund directed to one side only, 47. Serrate beset with small teeth on the margin, 83. Setose beset with bristles, 102. Sheath the tubular lower part of a leaf in grasses, 2. Spathaceous having a large bract enclosing a flower cluster, 104. Spiciform spike-like, 13. Spike an inflorescence with sessile flowers on an elongated axis, the older flowers being lower down and the younger towards the top, 13. Squarrose rough with outstanding processes, 120. Stipe a short stalk of a gynaecium, 90. Stipitate having a short stalk, 62. Stolon any basal branch which is disposed to root, 5. Striolate marked with very fine longitudinal parallel lines, 49. Sub-coriaceous somewhat leathery, 47. Subulate finely pointed, 121. T Triquetrous three-sided or edged, 47. Truncate as if cut off at the end, 60. Tumid swollen, 66. Turbinate cone-shaped or top shaped, 120. X Xylem the wood elements of the vascular bundle lying next to the phloem, 19. INDEX (Small i denotes Figure Numbers.) A Aerial roots, 6, 8i, 9i Agrostideae, 44, 220 Aleurone layer, 18 Andropogoneae, 44, 138 Andropogon, 15, 182 inflorescence, 13 annulatus, 204, 160i, 161i asper, 195, 155i, 156i caricosus, 201, 159i section of stem, 26, 33i, 34i contortus, 5, 207, 162i, 163i ligule, 13i foveolatus, 185, 148i, 149i monticola, 199, 158i pertusus, 5, 191, 152i, 153i pumilus, 188, 150i, 151i Schoenanthus var. caesius, 209, 164i Schoenanthus, ligule, 13i Sorghum, 6, 67, 8i section of grain, 20i, 21i Sorghum, section of root, 32, 45i, 46i, 47i squarrosus, 193, 154i Wightianus, 197, 157i Anthistiria, 211 tremula, 212, 165i Apludeae, 139 Apluda, 170 varia, 171, 142i, 143i Apocopis, 164 Wightii, 166, 139i, 140i Aristida, 221 Adscenscionis, 223, 171i, 172i funiculata, 229, 177i Hystrix, 226, 174i lodicules, 15 mutabilis, 228, 175i, 176i setacea, 225, 173i leaf structure, 36, 37, 38, 39, 54i, 55i Arundo Donax, 9, 10i Auricles, 11, 13i Axonopus, 46, 106 cimicinus, 108, 107i, 108i B Bamboo, 11 Bearded node, 9, 11i