720 
Thomas. — Seedling Anatomy of 
the apex they possess a large double bundle which lower down gives off 
a lateral on each side. The laterals unite with the central strand again 
some distance above the base of the cotyledon. The minute diarch root is 
formed very high up in the hypocotyl. 
Corydalis aura and C. lute a. The anatomical arrangements are very 
typical and call for no comment. C. lute a shows slight asymmetry in the 
fusion of its cotyledons. 
Capparidaceae. 
Cleome sesquiorgialis. This is an interesting form because it shows 
a much slower root formation than is characteristic of the cohort, or, in 
other words, complete root structure is only found lower in the hypocotyl 
than in most of the members of the Rhoeadales, and this is particularly true 
of the phloem arrangements — four phloem groups existing quite low in the 
hypocotyl. Examination of this species at different ages is very instructive 
as it shows that persistence of the degenerate resinous-looking remains 
of the protoxylem which enables the observer to determine its primary 
position in a comparatively old seedling. 
Cleome arborea is described by Chauveaud 1 as having fused phloem 
groups high in the hypocotyl. 
His figures show that the double 
bundle possesses three groups of 
primary xylem at an early age — 
the central alternate group and 
a group at the most remote point 
of each wing. This feature of 
C. arborea and the persistence 
of the four phloem groups in 
C. sesquiorgialis suggest the 
possibility of tetrarch allies. 
Capparis inermis and C '. ru- 
pestris . These species are good 
examples of the type. 
The cohort of the Rhoeadales as judged by some thirty- five species 
thus presents very uniform features in its seedling anatomy. The only 
suggestions met with of departure from this uniformity are in the neighbour- 
hood of the Brassicas and in the Cleomes. In the first a tendency to the 
formation of lateral strands in the hypocotyl recalls forms in which 
a tetrarch root obtains (e. g. Magnolia ), as also does the long separation 
of the phloem groups in the hypocotyl of Cleome sesquiorgialis and the 
marked production of protoxylem groups on the flanks of the double bundles 
of Cleome arborea. 
34 
33 
Text-figs. 33,34. 33, Cleome sesquiorgialis. 
Nat. size. 34, Capparis inermis. x 2. 
1 Loc. cit, 191 r. 
