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‘and broken up to form the inoculum. The conidia were shown 
-to germinate freely overnight in hanging drops of the same 
medium. During the experiment, the mango plants were kept 
out-of-doors. 
few c,c.’s of the spore suspension were placed by means of 
a sterile pipette among the soil around the smaller roots of one 
plant and in contact with the unwounded lateral roots of another. 
Two plants were inoculated in wounds in the tap-roots made by 
scraping with a sterile scalpel, and other two were similarly 
inoculated in the hypocotyls. Two control plants were wounded 
one in the roots, both lateral and main, and the other in the 
hypocotyl. After nine months, only one plant, one of the two 
inoculated in a tap-root wound, had shown symptoms of disease. 
The other plants, including the controls, were perfectly healthy 
and had thrown out pairs of new leaves. The diseased plant 
appeared to be dead ten days after wilting had commenced, and 
the Fusarium was recovered from its roots. The injured mango, 
therefore, could not be said to be immune to attacks of the soil 
Fusarium, but it was apparently much less susceptible than the 
cashew nut. This was not altogether surprising, for mango 
seedlings had been grown in beds adjacent to those from which 
the diseased cashew nut seedlings were taken, and they had not 
yet been found diseased. It was unlikely that the Fusarvwm was 
confined to only a few beds in a nursery of many similar beds 
separated from each other by narrow paths and containing many 
species of plants both economic and ornamental. It was, indeed, 
more than likely that: these plants were immune for the time, 
or only slightly susceptible, as was the mango, to the Fusarium 
ilt disease. The general health of the seedlings was a factor of 
importance in the continuance of the immunity of the plant, 
and seedlings disturbed by, say, the operation of transplanting 
might prove susceptible, expecially if they were subjected to 
root-pruning. Evidence bearing on this point is given under a 
later heading. 
Another species of plant belonging to the Anacordiaceae, 
Spondias lutea, L., the yellow mombin, was tested. Seedlings 
were inoculated in root wounds with the cashew nut Fusarium 
and, at a later date, others were treated similarly with a a 
of the Fusarium isolated from wilted Grevillea robusta 
The Grevillea strain did not prove to be pathogenic, but, in is 
case of the other, wilting began in five days and the plants were 
dead in eleven days. The Fusarium was recovered by the 
former methods. The growth in culture was typical of previous 
growths and, in addition, remarkable for the production of a 
. thick-set three-septate spore (Fig. 11) with stouter walls than 
usual which recalled the spore-production of the Nigella strain 
of the Fusarium, and for the presence of the rather scarce seven- 
septate conidium. On the damp-chamber material of Spondias, 
the Eobereptet spore was commonly associated with the 
