PARASITES 127 
by a small hole on the under side near the base. The 
walls of these chambers are covered with peculiar capitate 
hairs, which at one time were looked upon as glandular, 
secreting a digestive fluid for the purpose of consuming 
the bodies of minute animals which were unfortunate 
enough to find their way into the chambers. In this way, 
it was said, the plant obtained a supply of nitrogenous 
food. But it is now known that the toothwort is not an 
insectivorous plant at all; the capitate hairs are water- 
secreting structures—water-glands. The entire plant 
lives underground in soil where the atmosphere is 
always moist. Transpiration is, under these circum- 
stances, small, and the plant finds it difficult to get rid 
of excess of water. This is especially so in spring, when 
the roots of the host are drawing a large quantity of water 
Fic. 41.—Lathrea squamaria (ToOTHWORT), SHOWING UNDERGROUND 
SHOOT BEARING ScALE-LEAVES, ATTACHED TO THE Roots or HazEL 
By ABSORBING SUCKERS (a). (AFTER KERNER.) 
To the right a section through one of the hollow scale-leaves. 
from the soil for the use of the opening buds and expand- 
ing foliage. The supply of water to the parasite is conse- 
quently equally vigorous, and the plant gets over the 
difficulty by excreting the excess in liquid form by the 
glandular hairs. In June long spikes of pale, flesh- 
coloured flowers grow up through the soil into the air, and 
as these are the only parts that ever appear above ground, 
the plants are difficult to locate except when in flower. 
Glands similar to those found in the leaves of the tooth- 
wort occur in the subterranean buds of certain hemi- 
parasites—e.g., Bartsia—and may serve a similar purpose. 
(2) Orobanche.— This genus includes several species, 
nine of them British. They are brown scaly plants, 
attached to the roots of various hosts, such as grass, ivy, 
hemp, clover, etc. Some species confine their attention 
