33 2 
Holden. — Observations on the 
occupying what in a normal seedling would be the place of a second cotyledon 
(Fig. 6). In the simplest case the anatomy of the cotyledon is identical 
with that of one cotyledon of a typical dicotyl, its vascular supply consisting 
of a median ‘ double * bundle with a lateral on either flank. The behaviour 
Figs. 49-62. Figs 49-52, epicotyl of syncotyl showing total suppression of first epicotyledonary 
leaf on the symphysis side and two leaves only at the third no'de. Note the trimerous whorl at the 
fourth node. Figs. 53-37, a similar type of epicotyl in a Group II seedling. Figs. 58-62, cotyle- 
don bundles from the same seedling, showing anomalous bundle situated in the same vertical plane 
as the double bundle. Note the development of diarchy by the concentration of the lateral and 
marginal bundles on the anomalously situated bundle. 
of the median bundle is perfectly regular an.d it forms a root pole in the 
usual way. The two lateral bundles on entering the hypocotyl rapidly 
approach each other and unite to form a second root pole, so that a diarch 
condition obtains throughout the hypocotyl and root (Figs. 63-69). As 
a consequence the root whorl at the base of the hypocotyl is reduced to two 
