considered in Relation to the Phyllodc Theory. 31 1 
‘radial’ leaves, with four to eight angles or ribs, more or less resembling 
those of Hermodactylus. We may take the leaf of /. reticulata as an 
example. In the case of Hermodactylus the leaf is fairly symmetrical 
about a plane passing through the dorsal and ventral margins, but in the 
' "Radial’ Leaves inlridoideae 
Figs. 27-30. Fig. 27, Sisyrinchium juncezim , E. Mey., transverse section limb of leaf; 
pal., 3-tiered palisade parenchyma (x 23). Fig. 28, Acacia tereiifolia , Benth., transverse section 
phyllode ; pal., palisade parenchyma of about two tiers of cells ( x 23). Figs. 29 a-e, Hermodactylus 
tuberosus, Mill. ; m.l. , main lateral ; Figs. 29 a-c, sections from microtome series through base of 
leaf ( x 14) showing transition from closed sheath through open sheath to solid limb ; v.r ., ventral 
ridge; Fig. 29 d, mature part of another leaf ; k., keel; b. t and b. 2 , bundles of keel; lac., lacuna ; 
Fig. 29 E, section close to apex of same leaf; f, fibres; lac., lacuna crossed by trabeculae. 
Fig* 30 A-D, Iris reticulata, Bieb., sections from a series through base of limb of leaf (x 14). 
Fig. ''30 A and B, sheath; Fig. 30 c, transition region; Fig. 30 1), limb showing asymmetry of the 
two lateral faces, s and s', which meet at the ventral ridge, v.r. 
case of Iris reticulata this is not so. When the leaf is examined in situ , 
the flat surface (^, Fig. 30 D) has all the appearance of being an upper or 
ventral surface, but Figs. 30 A-D, drawn from a series of transverse sections 
through a leaf-base, show that the leaf is markedly asymmetrical ; the ridge, 
