250 PROCEEDINGS OF SECTION D. 
(6) the name and size of the Cobra. No such complete data has 
been published in Australasia. Much of the conflicting evidence 
offered by reliable witnesses on the subject of the ravages of the 
Cobra might be harmonised if the different factors above enumer- 
ated had been taken into consideration. 
It may be confidently stated that no timber impervious to ship- 
worms exists. The writer endorses a statement by E. O. 
Moriarty—“ In the pure part of the sea-water of this (Sydney) 
harbour I am satisfied that no timber that ever grew will resist 
the worm” (v). 
The fibres of endogenous plants, such as Palms and Bamboos, 
possess a high power of resistance, yet one shipworm earned the 
specific name of nuczvora, from its habit of boring cocoanut 
shells. The fossil wood and palm fruits (Nipadites) of Sheppy 
and Brabant are mined in the same way. Hardness is in itself 
no obstacle to perforation. 
Comparative immunity, such as is credited to the jarrah (Huca- 
lyptus marginata) is probably owing to the presence of aromatic 
essential oils repugnant to the mollusc (w). 
Continued submergence would be likely to abstract such 
essences by solution, and so weaken their defensive power. And 
it is also probable that such odours would be more effective 
abroad than against the native species accustomed to them. 
In the opinion of the late Baron von Mueller, the jarrah, £. 
marginata, best resists the shipworms, and next to that he 
ranked Lucalyptus rostrata (2). 
In New South Wales, authorities are generally agreed that 
the turpentine tree of New South Wales, Syncarpia laurifolia, is 
superior to all local timbers in ability to resist Cobra. Both 
the Cobra and the White Ant prefer the hardest Ironbark to the 
Turpentine. Maiden, who has published a full account and illus- 
trations of Syncarpia laurifolia (y), writes :—“ This immunity 
is believed to be owing to the layer of oleo-resin between the 
bark and the wood, which is distasteful to animal organisms, but 
we have no absolute experiments on this point.” The question 
was again discussed by Maiden and De Coque (z). They found 
two forms, locally distinguished as Black and Red Turpentine, 
the latter being the younger and more healthy state of the 
former, and yielding superior materials for piles. Timber grown 
on swampy land is inferior to that from well-drained hillsides. 
They were informed by Mr. C. W. Darley that “In pure sea- 
(v) Moriarty. Report to the Select Committee on Wharf Accommodation in Sydney 
Harbour, 1874, p. 44. 
(w) Laslett and Ward. Timber and Timber Trees, Native and Foreign, 2nd ed,, 1894. 
(xz) Mueller. Eucalyptographia Decades III. and IV. 
(y) Maiden. The Turpentine Tree, Agricultural Gazette of New South Wales, V., July, 
1894, pp. 463-7, Plate. 
(z) Maiden and De Coque. Report on Turpentine Timber with Special Reference to its 
Resistance to Cobra (Teredo). Agricultural Gazette, New South Wales, iii., Nov., 1895, 
pp. 733-743. 
