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conidia were not found in any of the cultures of the Fusarium 
isolated from cashew nut material, but they were noted previously 
in cultures of the fungus from Delphinium and Nigella.* They 
seemed to be produced only sparingly. After another fourteen 
days, Fusarium mycelial cushions bearing conidia were found at 
the leaf-scars of the stem. That the fungus progressed upwards 
through the tissues of the plants was proved by the examination 
of series of sections. Hyphae were found throughout in great 
abundance. It was rather remarkable that both plants should 
behave in an exactly similar manner despite the fact that contact 
between hosts and the parasite had been brought about in 
different ways. 
The plant which had been treated by placing the inoculum 
against the hypocotyl remained healthy and showed no signs of 
disease, but the plant with the wounded hypocotyl behaved in 
the manner detailed above for the root-treated plants even to 
the appearance of mycelium and conidia at the leaf-scars. The 
time development of the various stages corresponded toa day. 
e two remaining plants, 7.e., those with the inoculum placed 
within half an inch of roots and hypocotyl respectively, did 
not contract the disease although the former might have been 
expected to do so. Neither of them was as robust as the control 
plants, but neither developed the Fusarium in the damp chamber 
and in neither could the presence of hyphae in the tissues be 
demonstrated. It is possible that they might have proved to be 
diseased had they been left longer in the pots. Likewise, at a 
later period, one of the control plants appeared to be sickening, 
but a careful examination of it failed to disclose the particular 
symptoms of the wilt disease or the presence of a parasitic fungus. 
From the above experiments, it was concluded that, the 
Fusarium, a soil fungus, was capable of invading the smaller 
roots of young cashew nut plants with or without the help of a 
wound and the tap-root through a wound, and of causing death. 
It seemed, however, that the unwounded hypocotyl of the cashew 
nut seedling was impervious to the advance of the fungus—a 
statement that may stand further tests, if such were made, since 
the Fusarium is essentially a root parasite. Unfortunately the 
infection experiments were too few to justify sweeping deductions, 
although one has been made, but further work may be expected 
to strengthen the conclusion drawn with regard to liability to 
root-infection, for it is strongly supported by evidence from wilt 
diseases of other plants caused by soil fungi and by the evidence 
previously obtained from the study of the Fusarium on carnations, 
&c., and afterwards obtained from the Fusarzwm on Grevillea, 
CROSS-INOCULATION TESTS WITH THE CASHEW NUT FusaARIvUM. 
In view of the morphological resemblances between the 
Fusarium isolated from the carnation, Delphinium, Nigella and 
* loc. cit., p. 325. 
