256 Mr Barber, Parasitic Trees in Southern India. 
The double lines on Plate II represent the surface of the root 
attacked, the gland being always formed close to it. The dotted line 
marks the place where the collapsed layers are beginning to appear. 
It will be noted that here too the Olaceae differ from the rest. 
Lastly, comparing 1 and 6 as representatives of the two classes of 
haustoria, the cells near the root attacked are clear of contents in 
Olaceae and dense or full of starch and protoplasm in all the others. 
Plate III. Diagrams of various mature haustoria in Santala- 
ceae and Olacaceae. 7, Santalum album. 8, Thesium Wightianum. 
9, Buckley a Quadriala, after Kusano. 10, Osyris arbor ea. 11, Opilia 
amentacea. 12, Cansjera Rheedii. 13, Olax scandens. 14, Ximenia 
americana. 
In all cases the root attacked and split open is surrounded by the 
broad dark line. Of the haustorial tissues only the collapsed layers, 
cl, and the vascular tissue are shown. 
The upward ending of the collapsed layers is characteristic. This 
is opposite to the broadest part of the vascular loop in Santalaceae and 
Opilieae (7- — 12), but much lower in Olaceae (13 and 14: see also 
5 and 6 on Plate II). The interrupted zone of the vascular tract is 
very distinct in the Santalaceae and Opilieae, but is apparently absent 
in Olax and Ximenia. 
The structure and development of the haustoria of Opilieae re- 
sembles that of Santalaceae far more than that of Olaceae. 
