339 
The experimental block was situated only a few feet south of the main 
nursery experiment described in a previous paper.* All rows ran north 
and south, at right angles to the rows of the main experiment. Each 
row was 20 feet long and at first consisted of about 250 small seedlings, 
but these were thinned out until only from 130 to 150 remained. 
The seed for the experiment was received, through the kindness of 
Mr. S. D. Willard, from Vilmorin, Andrieux & Co., of Paris, in Febru¬ 
ary, 1891. It was imported mixed with moist sand and kept in the 
ice house until April 20, 1892, when it was sown in shallow furrows, 4 
inches wide by 2 inches deep, and covered with earth. Over the earth 
a thin layer of muck was spread. 
The fall previous the ground had been sown to rye, which was plowed 
under in the spring, before planting the seeds. The land had been 
occupied by potatoes the year before, but no fertilizers had been applied 
to it. Hence the soil was not in the highest state of fertility, and it is 
not surprising that in a part of the field only a feeble growth was made 
by the seedlings. The usual methods of cultivation were employed. 
The arrangement of the rows was somewhat irregular, but this was 
brought about in the attempt to separate all rows receiving like prep¬ 
arations by as much ground as possible. This method of treating 
duplicate rows has many advantages, and in fact should be considered 
as essential to the settlement of problems like the one here involved. 
A spraying apparatus of my own contrivance was employed, consist¬ 
ing of a small Johnson hand force-pump fastened into a papier mache 
pail by means of a thumbscrew. When many mixtures are to be em¬ 
ployed this apparatus has several advantages over the knapsack pump, 
the principal one being the ease with which it can be cleaned. With 
several feet of hose, rows of considerable length can be very effectually 
sprayed. The Vermorel nozzle with a lance was employed. 
In spraying care was taken that every leaf should be touched. The 
periods elapsing between the treatments were not long enough, it is 
believed, to allow the best mixtures to be washed off. In one or two 
cases it was found that the untreated adjacent rows had received 
occasional sprayings and it may be possible that an imperceptible mist 
was blown upon the control rows oftener than was observable, these 
being only 3 feet apart. It is believed, however, that this treatment 
of controls was so slight as not to vitiate the results in any way. The 
use of screens, made of light cloth or paper, to puotect the control 
rows during treatment, would obviate any such difficulty. 
The writer wishes to express his thanks to Messrs. W. T. Swingle 
and P. H. Dorsett, who assisted him very materially by suggestions 
and advice in the x>reparation of the fungicides. The preparations de¬ 
scribed below were, so far as my knowledge goes, first prepared by the 
parties above named. Those not mentioned were of my own invention or 
* Jour, of Mycol., vol. vii, pp. 240-264. 
