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214 PUCCINIA DIGIlAPUll)iS.
cismal Uredine, and that the host which bears the iiredo and
teleutospores is Phalaris arundinacea. Below is a condensed
account of my observations.
On June 13th, 1889, I appHed germinating spores of the
^cidium to the leaves of Cunvallaria mnjalis, MoUnia ccEndea,
Dactylis (jlomerata, and Phalaris arundinacea. When infected the
plants were in a healthy condition, and each plant was dealt with
in precisely the same way and covered by a bell-glass.
The first indication of a result was on June 24th, 1889, when
faint spots began to appear on the leaves of Phalaris arundinacea,
from which developed, on June 29th, small reddish sori of uredospores.
By July 4th several leaves were rusted over with uredo,
and on July 17th the first black sorus of teleutospores was evident
amongst the uredo. On Aug. 9th a great many of the black sori
were conspicuous on the withering leaves.
Not the least result followed on the Bactijlis, Convallaria , or
MoUnia ; and I may also state that Mr. C. B. Plowright, of King's
Lynn, infected Phragmites communis with spores of the jecidium I
sent him, about the same time, but without result. With germinating
uredospores— produced as above—I infected, on July 8th,
two isolated plants of Phalaris arundinacea; both had developed
uredo on July 24th, and on Aug. 11th the black sori of teleutospores
began to show, which by Sept. 14th were numerous. During
September I paid a visit to Bowness, Westmoreland,— a locality
where the secidium was abundant on Convallaria the previous
spring,—and found no trace of uredo or teleutospores on PJiragmitis,
MoUnia, or Convallaria, but I'halaris arundinacea w^as infested by a
Puccinia with here and there uredo still evident, which on microscopical
examination were very similar to those I had produced
artificially, and in some respects not unlike the teleutospores of
Puccinia sessilis and P. phalaridis, both species of which occur on
Phalaris arundinacea.
A number of leaves containing the teleutospores were collected
and placed under a bell-glass in a corner of my garden, where they
remained undisturbed throughout the winter. Later on (Oct.),
plants bearing artificially-produced teleutospores were similarly
protected by a bell-glass and kept apart.
During December, 1889, and January, 1890, several attempts
were made to cause the teleutospores to germinate, by placing a
number of sori in water, and keeping them in a temperature from
60° F. to 70'= F., but without success.
The first signs of germination v/ere on April 23rd, when a short
promycelium was seen emitting from two of the teleutospores.
Three days later germmation was more active, and at the end of
April I commenced the following experiments, which had been
carefully arranged beforehand :—
1. April 30th. — Actively germinating teleutospores from Phalaris
arundinacea were applied to the leaves of Convallaria and
Allium ursinum. On ]\Iay 8th spermogonia were visible on Convallaria,
which were succeeded by recidium cups, many of the