454 Arber . — On the Leaf Structure of certain Liliaceae , 
Figs. 14-19. Leaf structure of Johnsonieae. (Xylem, black; phloem, white; fibres, dotted.) 
Figs. 14 A-C, Sowerbeia juncea , Sm. Fig. 14 A, transverse section through leaf-sheath. Figs. 14 B and 
c, transverse sections through limb; st. = axial bundle-group. (All x 14.) Fig. 14 D, Clematis 
Vitalba , L. Transverse section of petiole for comparison with limb of Sowerbeia juncea , Fig. 14 c 
(x 14). Fig. 15, Sowerbeia laxifior a , Lindl. Transverse section of limb (x 23); b. = small addi- 
tional bundles. Fig. 16 A and b, Arnocrinum Drummondii, Endl. Fig. 16 a, transverse section 
of leaf-sheath (x 14) ; / l5 //, //', / 2 , lj, / 2 ", m lt m 2 = lateral bundles; m. = midrib. Fig. 16 B, 
transverse section of limb of another leaf ( x 14); lettering corresponds to Fig. 16 A (see Fig. 20, p.455, 
for one bundle-group on a larger scale). Fig. 17 A and B, Cercis Siliquastrum, L., for comparison 
with Arnocrinupi. Fig. 17 a, transverse section of petiole, showing steles B, b u and b 2 (x 14). 
Fig. 17 B, transverse section of base of lamina including midrib, m., and two main laterals, l x and / 2 
(x 14). Figs. 18 a and b , Johnsonia lupulina , R. Br. Fig. 18 A, transverse section of leaf-sheath 
( x 14) ; g. = fibrous girder ; a.p. = assimilating parenchyma. Figs. 19 a-c, Laxmannia grandijlor a , 
Lindl. Figs. 19 A and B, transverse sections in sheath region (x 14); lig. = ligule. In Fig. 19 a 
the wings of the sheath are omitted. Fig. 19 c, transverse section of the limb (x 23). For a more 
highly magnified drawing of the central bundle-group (st.) see Fig. 21, p. 455. 
