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COOPERATIVE OBSERVATIONS UPON RUSTS OF CEREALS.

It is with the hope of interesting more persons in the investigation of the rusts, and of being able tp place before the public other feets concerning these diseases than are possible to individuals working apparately, that I ask, for thecoming seasom, the cooperative observations and reports of ellow investigators upon the following general points:

1. Has the mycelium of any or all of the following rusts:
Puseinis grandnis, P. Rubigo-vera, or P. coronate succeeded in pass-
ing the winter alive in the tissues of their hosts, in your locali-
ty?

2. During what months of the past autumn and winter have you
noticed tredosporo pustules forming upon winter cereals? What
species of rusts?

3. Note date in spring when first new pustules of uredospores
are undoubtedly forming upon new plants. In other words, when
there are some indications that the disease is spreading from
plant to plant by means of the uredospores. In this connection
kindly note: (a) mean daily temperature, (b) if possible, atmos-
pheric humidity, (c) species of rusts

4. Note date of general infection of wheat and oats.
By general infection is menat that time (usually occupy-
ing from two to three days between the time of flowering and ripen
ing) at which red rust seems to become general throughout a given
locality. In connection with this, kindly note: (a) the direc-
tion of the prevailing winds for three or four days during first
period of general infection, (b_ mean daily temperature, and (c)
if possible, the atmospheric humidity, (d) the host plant and
the species of rust. (If there is doubt concerning the rust, a speci-
men will gladly be received and determined).

5. Miscellania: Any notes regarding rusts of cereals--vital
ity of uredospores, mode of first infection of host, etc.

At the close of the season the facts sollated from these co-
operative reports, together with my own investigations, will be
carefully edited and published in bulletin form, due credit being
given to all.

Yours respectfully,
signature

COOPERATIVE OBSERVATIONS UPON RUSTS OF CEREALS.

It is with the hope of interesting more persons in the investigation of the rusts, and of being able tp place before the public other feets concerning these diseases than are possible to individuals working apparately, that I ask, for thecoming seasom, the cooperative observations and reports of ellow investigators upon the following general points:

1. Has the mycelium of any or all of the following rusts: