PLATE X. 
Fig. 1. Part of the sucker, including the edge of one lobe, in a haustorium 
attacking the root of Plumbajo rosea. The contents are only 
drawn in some of the cells. Strands of vessels are formed in 
the sucker opposite to the vessels in the host’s xylem, and 
the cells adjoining these vessels are fuller of protoplasmic 
contents than the rest (pp). The cells at the side of the sucker 
(a) have ceased actively secreting and are cut off by a 
collapsed layer (c.l.) from the rest of the haustorium. Cork 
(ck) is formed opposite to these in the host’s wing. 
Fig, 2. A similar portion of an older haustorium attached to a root of 
Santalum album. The strand of vessels (vy) in the haustorium 
is not formed opposite to the vessels in the host’s root. The 
cells at the side of the sucker (a) are cut off by a collapsed 
layer (c.J.), and they are moribund and crammed with starch. 
Between these cells and the inside of the wing of the host’s 
bark there extends a broad layer of clear yellow substance (b). 
Near the sucker, this layer is striated and is apparently 
formed by the breaking down of the cells of the sucker: 
further out, the cells of the host evidently take part. The ¥ 
cells of the host’s wood are filled with dark brown substance. ; 
Fig. 5. A yourg haustorium on Abrus precatorius, which has successfully 
entered the host’s root and yet has withdrawn itself from 
the woody cylinder. The whole surface (a) of this part of 
the haustorium is composed of glandular cells filled with 
typical, dense, granular protoplasm, a structure usually 
confined to the cells lining the lumen of the gland. This 
specimen, which is unique among those examined, recalls those 
met with in the haustoria of Santalum album on Pterolobium 
indicum (Sant. I, fig. 34). Some of the cells are enlarged at a 
and b and show the position of the glairy secretion below the 
cuticle. 
Fig. 4. A haustorium attacking a root of Aerua lanata. The xylem (x) in 
this root is arranged in concentric bands separated by thin- 
walled parenchyma (p). A black “‘secretion ’’ separates the 
sucker from the host, but the section is interesting in 
showing that this layer is absent where the passage of fluids 
is taking place (a). The point of junction of the vascular 
systems of host and haustorium is drawn on a larger 
scale at a. 
