4 STUDIES IN ROOT-PARASITISM. 
considerable period. The fruit is said to be relished by birds, 
and would thus be carried from one tree to another and there 
dropped among the roots. We find a similar arrangement in the 
fruits and seeds of Santalum, Cansjera, Buckleya, and Osyris, 
while the smaller fruit of Thesxwm, surrounded by its fleshy 
calyx, falls at the base of the plant among the grass roots. Such 
thick-sowing ensures the presence near at hand of the roots of 
other plants and also explains the half-gregarious mode of 
occurrence so often seen in root-parasites. So in the Rhinan- 
thacee we hear of comparatively heavy seeds and germination 
of the young plants at the foot of their parents’ stems, forming 
the “milky ways” of the Eyebright and causing the Yellow 
Rattle to be found in such masses as to suggest their having 
been “ sown by the bushel.” ’ 
Upon germination the root emerges, carrying with it a 
warty mass of endosperm reminding of a carbuncle, becomes 
positively geotropic and passes downwards. The cotyledons 
increase in size and form two plates folded on one another in the 
endosperm (Plate I, fig. 4), their free surfaces developing a well- 
marked epithelial absorbent layer. A great extension of the 
hypocotyl now takes place and, as in Santalum, forms a green 
loop above ground connecting the root and seed. The cotyledons 
are soon broken off at the base and are left behind in the empty 
seed, while the young stem is borne aloft and the first pair of 
leaves unfolded. These stages are illustrated in figures 2—5 on 
Plate I. 
4. As it was not found possible to observe the seedlings of 
Olax in nature, a number of seeds were sown in pure sand in 
pots in a garden in Madras. In 40 days the young plants had 
attained a length over all of about six inches, a pair of small 
green leaves being unfolded two or three inches above the surface. 
Below ground a sinuous tap-root gave off secondary horizontal 
branches at intervals. The whole root-system at this stage as 
! Kerner and Oliver, Natural History of Plants, I, 184, 1894. 
