56 Sargant . — Theory of the Origin of Monocotyledons 
the hypocotyl, but a true cambial zone is still found in the 
upper part of the root. 
The vascular symmetry of this species is practically identical 
with that figured in Diagram IX as the normal Ranunculace- 
ous type. The only peculiarity which deserves notice is the 
precocious development of a cambium, and its extraordinary 
activity. This suggests that the growth of the hypocotyl 
into a spindle-shaped tuber, which is well marked at the 
end of the season, may be due to tissues added by the action 
of a normal cambium-ring. If so, the mature tuber may 
resemble that of Corydalis solida (Jost, 28). 
The seedlings examined of Anemone coronaria are all much 
older than those of Delphinium sp., whose structure has just 
been described. The vascular symmetry of their cotyledon, 
hypocotyl, and primary root is however identical with that of 
Delphinium sp. Much more secondary tissue is present, and 
the stele has become circular owing to the greater activity 
of the cambium opposite the plumular traces. The secondary 
tissues are continued downwards far below the level at which 
the stele has become root-like. At no level have I found 
lignified secondary tissue outside the two protoxylem groups 
of the central plate of primary xylem, but radial rows of five 
or six well-lignified elements are found on the outer side 
of the plumular metaxylem, forming buttresses as it were 
to the central xylem plate. The two phloem groups of the 
original diarch root-stele can still be identified, but they are 
isolated between the secondary tissues and the pericycle at 
a considerable distance from the centre of the section. 
The growth of Eranthis hiemalis from the seed has been 
followed by Irmisch with his usual care (24). Nothing can 
be added to his account of the external characters, but for 
convenience I will briefly describe a first-year seedling 
(PI. VI, Fig. i). The cotyledonary tube is very long, and 
the lower part is buried in the soil. Its base is inserted 
on a small tuber, which is spindle-shaped when first formed 
but later becomes globular. The plumule is quite rudimentary 
at this age : it is seated on the tuber and enclosed within the 
