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Transactions of the Boyal Society of South Africa. 
mon epidermis. The two must therefore have been united from a very 
early period of development. As the two plants were so intimately 
bound together they probably arose from the same archegonium ; each, 
possibly, from one of the two daughter nuclei resulting from the first 
division of the oospore. 
Although the epidermis and the cortex were continuous, yet the 
vascular systems of the two halves were completely separate, as shown 
in Fig. 2. There was no difference between the vascular structure of the 
two parts, and each resembled exactly that of a normal seedling. Each 
part of the root showed the usual diarch structure, and the transition 
from stem to root structure was very rapid, taking place just below the 
insertion of the seed leaves. 
In this seedling, and in two normal ones studied, the transition 
phenomena were different from those described for Widdringtonia mahoni, 
Mast., and W. tuhijtei, Eendle, by Hill and de Fraine.* In Widdringtonia 
cuioressoidcs the single bundle of 
the cotyledon was still entirely 
undivided when it reached the 
central cylinder of the hypocotyl. 
In this region the phloem forms 
a continuous ring, and the xylem 
of the seed-leaf traces becomes 
mesarch and finally exarch. 
When the latter condition ob- 
tains the phloem disappears oppo- 
site the two protoxylem groups, 
thus resulting in the typical 
diarch root. 
The splitting of the seed-leaf trace described by Hill and de Fraine 
(loc. cit.) for the two species mentioned above does not take place, nor 
does the transition from the hypocotyl to root in this species correspond 
exactly to that in any member of the Oupressinese as described by these 
authors, more nearly approaching that in Cephalotaxus pedunculata, Sieb. 
and Zucc. This indicates a greater simplicity of structure in W. cupres- 
soides than in the above-mentioned species. 
In conclusion, I may state that these investigations were carried out in 
the Botanical Laboratory of the South African College, Cape Town, under 
the supervision of Mr. W. T. Saxton, M.A.,to whom I wish to express my 
thanks. 
Fig. 2. — X = xylem ; P = phloem ; C cor- 
tex ; E = epidermis. The position of 
this section is shown by W in Fig. 1. 
(x 22.) 
* T. G. Hill and E. de Fraine (1908), "On the Seedling Structure of Gymno- 
sperms," I. An7i. Bot. xxii., 88, 1908. 
