273 
bellglasses, and covered by them continuously, except for the few minutes neces- 
sary to perform the infection, until the end of the experiment, so that the source 
of error from accidental atmospheric infection was reduced to a minimum. 
The culture of Peridermium pini on the common groundsel (Senecio vulgaris) 
has with me been one of the most difficult to perform. After several successive 
failures, however, I succeeded in two instances in producing the Coleosporium. 
By the infection of Poa annua with the spores of ecidium tussilaginis, the 
Puccinia poarum of Nielsen was in three out of four cultures produced—a Puccinia 
hitherto unknown in Britain. 
Perhaps the most interesting of the series, however, was the production of 
Aicidium zonale on Inula dysenterica (also a fungus new to the British flora) by 
infection with Uromyces junci. This was successful in every experiment. The 
actual demonstration of this hetercecism had not hitherto, I believe, been made, 
although Fuckel* had the strongest ground for believing it to exist. 
In one of these experiments some fragments of Juncus obtusiflorus, with 
numerous pustules of Uromyces, in active germination, on them, were placed upon 
the upper leaves of a plant of Inula dysenterica ; in the course of ten or fifteen 
days these leaves began to show the yellow spots, which were the forerunners of 
the 4cidiwm. By this time the plant had grown taller, and had developed fresh 
leaves above those on which the Juncus had been placed. The fragments of 
Juncus were then removed from the leaves, on which they had been in the first 
instance placed, to the healthy, recently expanded leaves above, where in due 
course the dcidiuwm was developed. It was very interesting to observe how the 
4icidium could thus be produced in successive crops. 
PopISOMA SABINZ AND R&STELIA CANCELLATA. 
Exp. 2.—Six pear seedlings had fragments of Podisoma sabine placed on each 
on 19th April; on 6th May the spermogonia of Restelia cancellata appeared on 
them. 
Exp. 6.—Three pear seedlings were infected on the 13th April with Podisoma 
sabine; on 24th April yellow spots appeared; on 6th May spermogonia were 
abundant on all three plants. 
Exp. 10.—Four pear seedlings infected with Podisoma sabine on 14th April at 
8a.m. On 6th May every plant had spermogonia on it. 
Exp. 25.—11th May. Some Podisoma sabine, which had been soaked for 48 
hours in water in a watch-glass, was placed on some leaves of a pear tree in Mr. 
T. Pung’s garden. Having some doubt of the efficacy of the material, these leaves 
were reinfected on the 25th May. On11th June spermogonia appeared on one leaf, 
There were many pear trees in this garden, but this was the only pear leaf on 
which the fungus could be found. This leaf was gathered during the last week of 
September, and exhibited at Hereford. It never got beyond the spermogonial 
condition. 
* Fuckel, Syabol. Mycol., p. 61, 
