348 
Report of the Botanist of the 
with 
An ascu 
spores, 
raphyse 
it, and live frt 
Magnified 2«.»o diameters 
Original 
with spores, and beside it two of the sterile fila- 
ments usually associated with such sacs, but of no 
interest in this connection, together with some 
free spores. The sacs and their accompanying 
filaments are ranged side b}' side in a uniform 
layer, which is for a while entirely surrounded 
by a black covering that the fungus forms in 
the remains of the dead leaf. When the spores 
are ripe the covering breaks away above the 
layer, and they are free to escape; this layer is 
always of the same depth, but of variable breadth. Figure 4 shows 
a vertical section through a leaf containing two small fruiting cavi- 
ties. The covering has already opened over the^enter of each. At 
this state of development the spores are ready to be ejected, and to 
be deposited by the wind 
on the surface of the green 
leaves of plum trees in the 
vicinity, to start anew the 
ieptoria condition, leading 
to the early destruction of 
the foliage. 
The report of last year 
advises to " spray the foli. 
showing a 8' e during May and June, 
or even longer, with some 
fungicide," and hyposulphite of soda or sulphide of potassium are 
recommended for trial. This suggestion was put to the test by 
using the latter substance, applying it in a solution of one-half 
ounce to the gallon of water, from May 25 to June 27. (The 
details of this experiment are given at another place in this 
report.) Very encouraging results followed, but it was evident, that 
for this season at least — the earlier part being unusually dry — 
the spraying need not have been started so early, and should have 
been continued longer. Septoria spots were not found on the leaves 
till about the middle of June, and the spraying need not have begun 
much earlier than this. Further trials will be needed to settle the 
details of the method to insure uniformly good results. 
^^^^ 
lap 1 
Wmmm 
Figure 4. 
Vertical section of two perithecia 
mature asei. Taken from a leaf gathered June 18. 
Magnified 110 diameters. Original. 
Sulphide ok Potassium as a Fungicide. 
Sulphur has been the general remedial agent with gardeners, horti- 
culturists and agriculturists for all disorders of plants, either due, or 
supposed to be due to the incursions of fungi, from a time much beyond 
