Cc. A. BARBER. 19 
outside the collapsed layers (Plate VI, figs. 1 and 5), but they 
are sometimes found along with crystals of calcium carbonate 
in the elongating cells of the inner cortex In a few cases, as 
stated above, the crystals are found inside them. 
THE VASCULAR SYSTEM. 
13. The general arrangement of the vas_ular system in the 
hausterium of Cansjera Rheedii is similar to that described 
already for Santalum and Olax. A branch from the vascular 
cylinder of the mother root spreads out to form a widening 
circle of bundles in the transitional region. At a certain point 
these bundles are broken up, and isolated rows of vessels, 
separated by parenchyma, are uniformly distributed over a 
broad circle round the central mass of ground tissue. This 
has been regarded as the region where the mother root joins 
the haustorium proper. Below it, the vessels are seen to 
branch repeatedly so that their number increases greatly. 
They are, moreover, no longer separated, but fuse to a dense 
mass of xylem arranged in a broad oval ring. This ring rapid- 
ly flattens downwards, at the same time becoming discontinu- 
ous at two opposite points, so that, ultimately, two parallel 
lamelle are formed which pass down the axis of the hausto- 
rium. This is the arrangement in Santalum: it will be remem- 
bered that in Olax only one plate of vessels is found in the axis 
of the haustorium. Lastly, the bundles become broken up 
again and the vessels form separate rows in the sucker as it 
approaches the host’s root. A closer study of this general 
arrangement need not detain us longer, as it has been fully dealt 
with in previous papers (Sant. II, Plates IV and VI—VII]I) 
Certain parts of the vascular system are, however, pecu- 
liar in Cansjera haustoria. The endodermis, occasionally 
noted in Santalum, but of so problematical a nature in Olaz, 
is very clearly defined. The interrupted zone described in 
Santalum, but totally absent in Olax, has its greatest develop- 
ment in Cansjera. As in Santalum, no bast is found in the 
