Primitive A ngio sperms . 1 8 1 
well sheltered from adverse conditions by the end of its first season, it will 
not survive to the next. Geophilous seedlings take shelter in the earth. 
Hence their underground organs are of the first importance. A bud must 
be formed, protected both by its coverings and by the soil in which it is sunk. 
It must be provided with food on which to start growth when the genial 
weather returns. The provision of such a bud in the limited period allowed 
to the seedling taxes its resources. Only a very small aerial shoot can be 
afforded in addition, even though in the end the green parts more than pay 
their way. 
The first question proposed on page 179 has been already answered. 
The geophilous habit is correlated with partial fusion of the two cotyledons 
in some Dicotyledons, and with a single cotyledon in others. Supposing 
one branch of descendants from the Primitive Angiosperms to become 
geophilous, the green parts of their seedlings would inevitably be reduced 
in the early seasons of growth. In the first season this reduction might well 
take the form of partial fusion of both cotyledons, leading to complete fusion. 
The second question can perhaps be answered most graphically by 
describing a concrete instance. The seedling of Podophyllum peltatum has 
been fully described by Mr. Holm (45). Its cotyledons are united into 
a long tube : the blades alone are distinct. We have already seen that its 
vascular symmetry recalls that of a Monocotyledon (p. 173, and Figs. 19- 
21). The anatomy of the erect stem in the mature plant is markedly 
Monocotyledonous (Holm, 45, and Solereder, 81, p. 52). The radical 
leaves are net-veined, but their petioles are expanded at the base into 
a sheath from which many traces enter the subterranean stem-bud. 
Mr. Holm has shown how the scattered disposition of bundles in the stem 
follows from this arrangement. The traces in the erect stem have lost 
their cambium — they are closed like those of a Monocotyledon — but 
cambium is found in the bundles of the rhizome. These are arranged 
in a single circle, but without intrafascicular cambium. 
Podophyllum peltatum grows in swampy woods in the Southern States 
of North America. Its squat underground axis, packed with starch, though 
not expanded into a tuber, is a geophilous character, probably developed 
under climatic conditions of greater severity than those of its present habitat. 
There are bulbous plants in English woods — the bluebell, Scilla festalis , 
Salisb., for example — which are above the ground in spring and early 
summer only. At this season such plants are sheltered by the leafless 
trees without losing much light. But though their geophilous habit 
enables these species to take advantage of the woodland stations which 
they now occupy, it was probably acquired elsewhere : inherited perhaps 
from ancestors living under more stringent conditions. In the case of 
Podophyllum this is the more likely as the only other species of the genus, 
P. Emodi , is Himalayan. 
