ON THE HETERCECISM OF THE UREDINES. 
9 
made subject of experiment ; some of the most strikingly suc- 
cessful were made with Podisoma juniperi , which produced the 
Rcestelia so abundantly as to cause the death of young hawthorns 
operated upon. It is proposed that an epitome of all these experi- 
ments be read at some of the Hereford meetings next October, 
tv hen no doubt they will be fully criticised. Of course to those 
botanists who have already accepted the hetercecism of the Uredines 
these experiments will appear to be a work of supererogation, and 
a mere waste of time, but it must be remembered that many of us 
in this country have hitherto either declined altogether to accept 
the theory until further evidence was forthcoming, or else believed 
it in a half-hearted, provisional sort of way. It is hoped that this 
year’s work has not been thrown away, but that those who were 
doubtful upon the point may see their way to accept it. Personally 
my own feelings, when this year’s experiments were begun, were 
biased against it by the unsatisfactory result of the 1881 experi- 
ments. But by investigating the life-history of more species, 
especially such as are uncommon, where the liability to acci- 
dental infection was practically nil, the accumulated evidence 
became irresistible. It is worthy of notice that no less than 
three Uredines which were hitherto not known to be British were 
by those experiments brought to light, viz., PEcidium zonale , Duby, 
on Inula dysenterica ; Puccinia magnusiana, Kornicke, on Phrag- 
mitis communis, hitherto regarded as a variety of Puccinia graminis ; 
and Puccinia poarum, Nielsen, a fungus I have for many years 
known both in the Uredo and Puccinia form, but always regarded 
as a form of Puccinia coronata. 
It is needless to add that our acceptance of heteroecism will 
entail a complete rearrangement of the Uredines , and it is hoped 
that a paper on this subject may also be submitted to the members 
of the Woolhope Club. 
Had it not been for the kindness of my friend M. Cornu in 
giving me directions and hints as to the manner of conducting 
these experiments, we might have gone on in our old groove for 
some time to come — a proof, if any were needed, of the utility of 
our autumnal conferences. 
Ol course these experiments — amounting, as they do, to more 
than a hundred — have entailed some little work, and although 
there is no pretence of originality about them, yet the satisfaction 
of being able to see the germ-tube of a spore of Mcidium berberidis 
insinuating itself into the stoma of a wheat leaf, which I first 
watched at a very early hour one summer morning, was “ pretty 
considerable.” 
Charles B. Plowright. 
