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In this ease there is vascular connection between host and parasite. 
It has been said that the Mistletoe may be more symbiotic than 
parasitic when it is on deciduous trees because it is evergreen and 
assimilates carbon dioxide in the winter when the host tree is 
leafless. The greatly decreased fruit crop in attacked apple trees 
proves that any symbiosis is greatly outweighed by the parasitism 
of the mistletoe. A more complete state of parasitism is shown 
by Cassytha, the Bush Dodder, which is common throughout Aus- 
tralia. This is a twining plant with green leafless stems. From 
the point of contact of its stem with the host arise haustoria. 
Here again there is vascular connection between host and parasite, 
the woods and phloems of each uniting. Cassytha is parasitic for 
both organic food materials and transpiration water containing 
inorganic salts. Both the Mistletoe and Bush Dodder are aerial 
parasites. The natural order If hinanthaceae is notorious for the 
number of root parasites amongst its members. These, like Nuyt- 
sia, appear to have quite enough leaves to supply all the organic 
material necessary, but nevertheless need root connection to en- 
able them to reach maturity. Their root system connects with 
that of the host root by means of disc-shaped haustoria. The 
fleshy ring giving rise to haustoria, as found in the Christmas Tree, 
is unique. The seeds of Orobanche, the Broomrape, another exotic 
root parasite, will only germinate when in contact with the roots 
of a host plant. This is certainly not the case with Nuytsia, the 
seeds of which will germinate out of contact with any host root. 
Seedlings are very rare and generally die off young. The 
survivors owe their success to having obtained connection with a 
host root early, while early death is often due to the failure of 
the root to find a host and the failure of the leaves to provide all 
the organic food materials necessary. One seedling at Mount 
Lawlev was found to be drawing on the stem of the couch grass 
(Cynodon dad y Ion). This is interesting because it goes to show 
that the parasitic attacks of Nuytsia are not limited to roots. 
Seedlings may readily be distinguished from suckers by their 
stems, leaves, and rate of growth. The sucker appears above the 
ground as a stem about a quarter of an inch thick and grows 
rapidly so that in a year it is about four (4) feet high. Its pale 
leaves are few and sparsely scattered. A seedling, on the other 
hand, has a much thinner stem more closely beset with leaves, 
which are a brighter green than those of the sucker. One would 
expect the seedling to have more leaves and for these to contain 
more chlorophyll because it is more dependent on its own resources 
than is the sucker which has the reserve food material of the 
parent underground stem to draw on. The growth of the seedling 
is also much slower, a year-old seedling being several indies only 
in height and this is attributable to the same cause. Numerous 
