92 Sargant . — Theory of the Origin of Monocoty r edons. 
PLATE VI. 
Eranthis hie?nalis. 
Fig. i. Outline of seedling A 6y drawn from life, x %. (E. S.) 
Fig. 2. From microtome series through seedling A 2 . Transverse section of. 
embryonic stem-bud enclosed within base of cotyledonary tube, x 113. 
Fig. 3. From same series, *09 mm. below Fig. 2, passing through top of tuber. 
Each trace from the cotyledon, C l} C 2 , shows double structure, x 113. 
Fig. 4. From same series, *io mm. below Fig. 3. The two pairs of bundles 
are drawn side by side ; the xylem of each is in three groups, x 113. 
Fig. 5. From same series, -07 mm. below Fig. 4. Four phloem and eight 
xylem groups, x 113. 
Fig. 6. From same series, *73 mm. below Fig. 5, approaching the base of the 
tuber. The scattered traces have gathered together, and now form two phloem 
and four xylem groups. Three of the latter are complete : the fourth is forming 
to the SW. of the section, x 113. 
PLATE VII. 
Eranthis hiemalis. 
Fig. 1. From same series as Fig. 6 on Plate VI, and -27 mm. below it. 
Between each of the two phloem groups and the xylem internal to it, there are 
a few unlignified secondary elements in a radial row. px ' , px' y are the two groups 
of protoxylem within the phloem groups, which will disappear lower down, 
x 200. 
Fig. 2. From same series, *15 mm. below Fig. 1, through top of primary root. 
Diarch root-stele ; the groups px' y px’ , have disappeared, x 200. 
Fig. 3. From microtome series through older seedling A 5 . The section passes 
through the base of the tuber. Tetrarch xylem-plate. The elements px ' , px? are 
primary, x 200. 
Ranunculus Ficaria. 
Fig. 4. Outline of seedling A 3 , drawn from life, x %. (E. S.) 
Fig* 5 * Outlines of the cotyledons from three seedlings, A 3 , A iy B lt showing 
the venation of the blade, x 2. (E. S.) 
Fig. 6. From microtome series through seedling A 3 , cutting axis near insertion 
of first cauline root. The slender plumular trace in the upper part of the section 
is approaching the larger trace from the cotyledon in the lower part, x 100. 
Fig. 7. From same series, .09 mm. below Fig. 6, cutting axis at first node. 
The trace from the cotyledon is cut longitudinally as it approaches the plumular 
trace. Its double structure is clear, and the plumular trace is branching in two 
directions to meet it. x 2 50. 
Fig. 8. From same series, only *03 mm. below Fig. 7. The diarch root-stele is 
almost complete. The lower protoxylem group is from the cotyledon ; the upper 
one from the plumule, x 250. 
