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D. Stem wound. June 2. The two lower leaves are yellow, the 
two upper ones lighter green than normal. June 6th. 
The two yellow leaves have fallen off. These are the 
two just above the wound, but do not show any signs of 
fungus. The fall may be normal. The wound seems to 
be commencing to heal the, edges curving in, but the 
centre portion looks dead. 
E. Young leaves smeared with spores. June 2. One of the 
young leaves wilted and turned black. June 6, the 
other young leaf was wilting. It fell a day or two later. 
The first mentioned had, by June 6, developed a number 
of black pustules. I examined these and found a number 
of pale spores not transversely divided and a few black 
spores exactly like those of typical Diplodia. Eventually 
it was attacked and destroyed by mildew. 
F. Bud cut off. June. 2. The uppermost leaf is yellow and 
falling. June 6. This leaf has fallen and the petiole is 
covered with conical black pustules, scattered all over it. 
A few days later, they commenced to produce spores in exactly 
the same way as in the original stem, in the form of strings of sooty 
black Diplodia spores quite typical. 
In plant A., on June 20, I observe that the wound has not yet 
healed. The centre has sunk and three longitudinal cracks extending 
into the otherwise healthy bark have appeared. There is no sign of 
repair along the edges of the wound, but on the uninjured portion 
below and above the wound there is a blackish colouring. One of 
the cracks contained a minute quantity of black substance from 
which by scraping I obtained one Diplodia spore. The fungus 
appears to be progressing, but slowly. 
In the others in which the cut bud was infected, the disease has 
apparently quite stopped. The plant D has not yet healed the 
wound. On June 20th. I cut off the tops of the two check plants 
which were perfectly healthy, C and G, and placed a quantity 
of spores, from the same specimen with which the other experiments 
had been conducted on the cut end. On July 2, I find both affected. 
In C, about half an inch of the top below the cut is dry and brown. 
In G. the top is dry and brown for one inch and is producing fully 
developed pustules in abundance. Thus the life history of the plant 
is not more than a week long. 
Several points are noticeable about these few observations. In 
the first place the rapidity of the growth of the fungus is remarkable. 
It commenced to germinate in twelve hours, and a leaf stalk infected 
through the wound in the bud, in six days is killed, May 28 to June 
2, and in about 4 days more produces spores. 
Secondly. No preliminary infection by Gloeosporium is 
necessary. 
