FLOWERING PARASITES 185 
one should say correlatively, retained their 
leaves, and all the complexity of structure 
which, as we have seen, the presence of the 
green leaf entails. 
The parasitic habit has appeared inde- 
pendently in a number of other families of 
flowering plants. In some of them it is char- 
acteristic of practically all the members, 
just as in the Loranthacez mentioned above. 
As a matter of fact, in very many of the 
larger natural orders or families we also find 
species which have more or less broken away 
from the ranks of typical green plants in con- 
nection with their assumption of saprophytic 
or parasitic habits. Sometimes we can 
construct, within the limits of nearly related 
groups, all the stages, starting from a sort 
of dalliance with robbery which is hardly 
betrayed by any essential structural change, 
but culminating in species which, so far as 
their vegetative structure is concerned, have 
lost all resemblance to the forms of higher 
plants. 
Thus in the alliance or family to which 
the snapdragon belongs, the familiar little 
Kye-bright (EKuphrasia), abundant on grassy 
downs, the pink Lousewort (Pedicularis) of 
the marshes, and the yellow Cow-wheat 
(Melampyrum) of the woods, all have begun 
to supplement the legitimate stock of food 
which they manufacture for themselves by 
stealing from adjacent plants. This they are 
enabled to do owing to the ability they possess 
