October 24, 1885. 
THE GARDENING WORLD. 
117 
the very decided opinion of some observers on this 
point, there is every reason to believe that it will prove 
to be as useful in combating “club” in the Cabbage 
tribe and other plant ailments. Whether club is due 
to a fungus (the German notion), or to insects (a moot 
point at present), there can be no doubt of its hurtful¬ 
ness, and any real remedy for it will be warmly 
welcomed by everyone. 
Fortunately in one respect, but unfortunately in 
another, I cannot speak from personal knowledge of 
the value of sulphide of potassium, for I have neither 
had mildew npr club this year in my garden. But I 
have had such reliable testimony from trusted corres¬ 
pondents as to its value, that I have no hesitation in 
asking gardeners everywhere to test its qualities, and 
report upon its merits or demerits, as their experience 
may justify. And here I may say that I have no 
interest whatever in drawing attention to the subject, 
other than the, interest which every gardener must 
always feel in whatever may prove beneficial to his 
fellow gardeners—amateur or professional. 
One correspondent has pointed out that sulphide of 
potassium is a reliable remedy for the green mossy 
growths on the tiled floors of greenhouses and conser¬ 
vatories, where their presence is at present too often a 
disfiguring feature. Indeed, it seems to me that this 
chemical is likely to prove itself in the near future a 
veritable gardener’s friend. No one can at present 
appraise its utmost value ; and as it seems to be in no 
way hurtful to the foliage of the most delicate of our 
ornamental plants if used in proper proportions—£ of 
an ounce to a gallon of water—it behoves every one to 
experiment with it tentatively on everything. 
But here it is perhaps as well to say a word of 
caution. There is more than one quality of suljihide 
of potassium ; there is the ordinary article of commerce 
—mostly made in Germany—and there is the carefully 
prepared substance w'hich I have been in some degree 
instrumental in distributing. The latter is manufac- 
by Messrs. Philip Harris & Co., of Birmingham, and 
this I am assured, on the best authority, contains a 
much larger proportion of soluble sulphur than the 
common kind, and I am of opinion that to the solu¬ 
bility and amount of the sulphur its success is due. I 
have no desire to advertise the wares of one manufac¬ 
turer more than of another, but I think this is a case 
where the special attention paid by the manufacturers 
in question, in making a substance likely to be a 
substantial boon to a community in such a way as to 
give the best practical results, justifies the mention of 
those, to whose care and enterprise the community are 
indebted for the extra qualities of the substance under 
consideration. 
I saw a letter this morning from one of our most 
eminent practical gardeners, written spontaneously, in 
which he states that two dressings of the sulphide of 
potassium solution in his hands entirely eradicated 
mildew on Cucumbers and Boses. Were 1 at liberty to 
publish the name of this gentleman, it would carry 
conviction to the minds of everyone. I urge every 
gardener to give this new remedy a trial and then to 
re 2 )ort the result. If my friends discovery is as valuable 
as many who have tried it believe it to be, it is one of 
the most important of modern times, so far as the 
gardener is concerned .—Edward W. Badger, Moscly, 
near Birmingham, Oct. 21 st. 
-- 
HYBRID RHODODENDRONS. 
What a remarkable collection of these Messrs. 
Yeitch & Sons had at South Kensington on the 13th 
inst. They illustrated the newest things in this way 
that this spirited firm has produced. When anyone 
compares the size, substance, and rich colouring of the 
flowers seen in these new forms, and those which 
characterised the original types of B. javauicum, and 
B. retusum from the Java mountains, then some¬ 
thing like an accurate idea can be formed of the advance 
which has been made. The collection shown by Messrs. 
Yeitch & Sons, though limited in numbers was strong 
in newer varieties. Two of them were awarded First 
Class Certificates of Merit, viz., Apollo, a great beauty, 
pale but bright orange with a dash of buff; pip and 
truss very fine. This variety shows in a remarkable 
degree the great developement in regard to size and 
stoutness of texture which characterises the more recent 
seedlings. Equally fine is Minerva, which, like Apollo, 
is very large and bold in the flowers, with finely formed 
segments ; colour bright yellow, faintly tinted with the 
most delicate red ; extra fine. 
The deepest coloured variety was Duke of Connaught, 
a dull red, but a very good and showy variety, though not 
so bright as Cardinale, a late introduction, large and 
bright; quite a tiny plant of this, not more than 4 ins. 
in height was seen bearing a fine truss of flowers. 
Crown Princess of Germany is of a buff ground, flushed 
with bright cerise on the edges, very distinct and good. 
Queen Victoria is in the same way but paler, and very 
pretty. Princess Frederica is pale canary buff, the 
segments very narrowly edged with pink. Duchess of 
Connaught is clear pink, with the colour a little deeper 
on the edges of the segments ; distinct and very good. 
Maidens Blush is of a delicate blush, with a decided 
edging of pink to the segments ; lastly, Princess Alex¬ 
andra is of a most delicate blush, very chaste and 
pretty. 
THE MOVEMENT OF PLANT 
ORGANS. 
The opening lecture of the Ealing Microscopical and 
Natural History Society, was delivered recently by the 
Eev. G. Henslow, who took the abovesubject for his text, 
and gave a very interesting and instructive address. 
Movement, said the lecturer, was formerly considered to 
be a distinguishing characteristic of animal life, but this 
view had long ceased to be held, since many plants, 
more especially among the microscopic fungi and alg;c, 
were in a constant state of movement. The first organic 
movement specially described was that of the radicle. 
Everyone is familiar with the bean or pea, and know 
that they consist of two halves, which when germina¬ 
tion takes place, becomes the two first leaves, while 
the rudimentary stem known as the radicle passes down 
into the earth. Its power of movement is very remark¬ 
able ; it will pass over, through, or around almost any 
obstacle, and in one case of which a drawing was shown, 
the root of a radish had tied itself into a complete knot. 
The effects of moisture in determining the movement of 
plant roots was dealt upon in some detail, and the com¬ 
mon idea that roots go in search of water was shown to 
be erroneous. The upward movements of the plant 
stem was next described, and the “banding around” 
movement by which a plant stem climbs was fully 
desciibed. Some of the various methods of climbing 
by leaf and tendril were then referred to, and one re¬ 
markable instance of a Virginia creeper which lifted 
up a water bottle in the course of its climbing was 
narrated. The effect of gravitation in determining the 
direction of movement in a growing plant was also dis¬ 
cussed. 
Mr. Henslow next went on to speak of the move¬ 
ments of leaves under varying conditions of light and 
temperature, and explained that in those cases in which 
the movement resulted in closing, the probable expla¬ 
nation of the change of position was to be found in the 
fact that in the altered posision the upper surface of the 
leaf was protected from the injurious effects of cold 
resulting from radiation. The complicated and beauti¬ 
ful movement of the leaves of the comman clover in 
folding at night were minutely described, and also the 
folding together of the leaves of the sensitive plant 
(Mimosa pudica), and of the wood sorrel (Oxalis aceto- 
sella). In some plants it was also stated that a 
periodic movement of the leaves took place, for example 
in the Indian plant known as Hedysarum gyrans, in 
which a peculiar movement of the leaves takes place 
every few minutes. Some of the movements may be 
induced by touching as well as by change of tempera¬ 
ture, as for instance in the case of the sensitive plant. 
The folding of the leaves may be truly called a sleeping 
of plants. Professor Henslow then proceeded to describe 
an investigation in which he had been engaged during 
the pvesent year, and of which the results had recently 
been published by the Linnean Society. He had ob¬ 
served closely the method in which the leaves of plants 
were folded while yet in the bud, and had, by a long and 
careful examination, discovered that the plan of folding 
was the same as in the plants previously described, and 
as a result of these observations he had been led to in¬ 
fer that the object of this folding was to protect the 
delicate upper surface of the leaf from the injurious effects 
of cold resulting from radiation, especially during the 
night. The folding together of some leaves was so 
close that it was impossible to separate them without 
injury. When once the leaf-bud had unfolded, the 
leaves did not re-fold in the same manner, but a lesser 
degree of folding was to be observed until the midrib 
had become so thick as to prevent anything but a par¬ 
tial folding taking place. The lecturer suggested that 
the members of the Society should make further obser- 
servations in the same direction. 
Professor Henslow then went on to describe move¬ 
ments which take place in flowers, and particularly 
mentioned a flower known as the fly catcher, in which 
the flower encloses any small insect which may happen 
to come within its clutches. The holly-leaved Berberis 
was also described, in which the stamens move towards 
the centre of the flower and assist the fertilisation by 
throwing the pollen upon any insect which may visit 
the flower. The movements by which some plants 
bury the seed vessel were then described, and the case 
of the Cyclamen specially noticed, in which the seed is 
found to possess the power of absorbing nutriment 
direct from the soil after it has been buried, only those 
seeds which have been thus treated attaining full 
Odontoglossum Hallii magnificum. 
