A NOTE ON THE WOOD OF GNETUM 
GNEMON 
By MARY R. H. THOMSON, BA. 
Croll Scholar of the University of the Cape of Good Hope. 
(With 1 plate.) 
Some specimens of the wood of Gnetum gnemon, including pieces of an 
old stem 45 cms. in diameter, were received in this laboratory from Mr I. H. 
Burkill, of Singapore. Mr Burkill states that “ the specimens are parts 
of a horizontal branch. Where these branches are joined to the trunk there 
are curious thickenings extending partly round the trunk as if a knotted 
cord were under the bark.” 
Existing accounts of the detailed structure of the wood of Gnetum either 
describe anomalous zones of thickening as in G. scandens 1 or refer to a stem 
with a much smaller development of woody tissue 2 than is shown by this 
specimen. 
In the largest piece the secondary xylem extends continuously through 
a radius of almost 2 cms. and there is no sign of anomalous cambium 3 . 
Also there are no indications of annual rings, and therefore no data on which 
the age of the specimen may be determined. 
The pith shows a diameter of 02 cm. and the peripheral region including 
phloem, cortex, and bark extends through 02 cm. 
The medullary rays are very conspicuous and somewhat wavy in their 
course, broadening considerably as they reach the periphery of the wood. 
Pith. 
The pith consists of slightly elongated cells lignified in the region of the 
vascular bundles, the lignified cells showing simple pits. Starch is present 
in the cells of both node and internode and calcium oxalate in addition 
in the node. The central pith cells of the internode become disorganised. 
1 De Bary, 1884, fig. 233, p. 586. 2 Duthie, 1912, p. 593. 
3 Cf. Eichler in Pfl.fam. p. 121. 
A. B. H. II. 
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