248 PARASITISM OF CUSCUTA AND OROBANCHE 
'The parasitism on this presents a considerable difference 
from that of Cuscuta, in the first place it is limited to the 
radical system; in the second place the absorption of the 
juices is effected by the central, not by the circumferential 
system. 
'The roots consist of a central vascular fascicle of ducts, 
this is surrounded by cellular tissue, containing a great quan- 
tity of amylaceous granules, as usual very irregular in size. 
These granules only, however, exist in abundance about 
the suckers. 
Of each sucker a gonflement takes place, and the face of 
the root is applied to the root in the shape of a disc, which 
has no determinate direction with respect to the root to 
which it is attached. From the fascicle of ducts opposite the 
centre of the swelling, ducts pass of, penetrating through 
the outer system of the root of the nourisher, and. expanding 
in the form of a pate d’oie on the outside of its ligneous 
system, and at this part the ducts are unrollable, elsewhere 
except perhaps towards the ends of the radicles, they are 
not so. 
: Pl. 61. figs. 11, 12. 
lla. Outer system of stock and mode of expansion of ducts. 
115. Central and outer system (on one side) of the stock 
and adhering ducts of the parasite. 
12. Mode of adhesion. Wood filled with granules. 
Here again we receive light on an obscure physiological 
point, viz. the functions of ducts. As the attachment exists 
only by means of ducts, it follows that ducts in this plant, are 
the only organs of what is analogous to the ordinary radicu- 
lar absorption. 
There is a similar tendency to mutual adhesion between 
the radicles of the parasite as in Cuscuta. 
The radicles are very brittle, and were anastomosed in one 
instance, such is easily imaginable provided the sucker's neck 
becomes elongated. 
I do not know on what plant the specimen from which the 
sketches were made was growing, as nothing but its root, 
(which was an exorhizal fibrous one,) was detectable. 
