CONTINENTAL GARDENS. 
307 
" I suspect tLat the germen is very speedily 
fertilized when the dust has touched the 
stigma ; but I doubt Avhether, after being 
fecundated, it is closed against any further 
impression. Mr. Knight has assured me that 
by touching the stigma of a smooth cabbage 
with the dusts of a curled and of a red cab- 
bage, he had given both the curl and the red 
colour to the seedlings ; but I am uncertain 
whether both dusts were applied at the same 
time. It would be very desirable to ascer- 
tain by experiments how long after the stigma 
had been touched with pollen a second im- 
pression could be given. I wished to try 
the possibility of crossing a plant of Pancra- 
tium littorale, which had twenty-one buds on 
a stem, with Crinum, Nerine, and Corburgia. 
The first flower had expanded before I had 
taken out its anthers, and though I could not 
distinguish any dust on its stigma, wishing to 
make my experiments with certainty, I im- 
mediately cut the flower off so low as even to 
take off the summit of the germen, which I 
thought I had destroyed, the embryo seeds 
being partially exposed. The anthers wei-e 
successively taken out of the twenty other 
buds, to which various uncongenial dusts 
were applied in vain ; and the only seeds 
produced were from the germen of the flower 
which I had so cut off, and I raised true 
plants of Pancratium littorale from them. 
This proves the fecundation to have been 
speedily effected, unless the germen could 
have been fertilized by dust having actually 
fallen into it accidentally when I cut off the 
flower. I have been unsuccessful in obtain- 
ing mule Convolvuluses, Hibiscuses, and 
Turneras, and I attribute this to some difl[i- 
culty in ascertaining the right moment for 
impregnating fugacious flowers. I have 
opened the buds before expansion, to take out 
their anthers, but the result has been a failure 
of seed. I did raise one mule between the 
red American Convolvulus sepium and Con- 
volvulus candidans, but it was very weakly, 
and died. 
" I believe it is an eiror to imagine that 
pollen will always retain its fertilizing powers 
for months if kept dry; on the contrary, I 
have found it quickly lose its virtue, entirely 
so the moment it became dry. The pollen 
consists of minute vesicles filled with a juice 
which is very visible by means of a micro- 
scope. The vesicles soon become dry, and 
though they retain their form, no juice can 
then be pressed from them ; nor have I ever 
obtained seed by means of any dust that was 
not fresh from the flower." 
Pollen to be kept long must be kept air 
tight, so that it cannot lose its moisture : but 
we believe it can be kept for a very long 
period. The pollen from dried specimens 
has been used, and we believe with effect, 
although it can hardly be proved until they 
produce flowers, when it will be seen whether 
there is any of the habit of the one from which 
the pollen was taken. There is no doubt, 
however, that pollen may be kept without 
losing its properties if proper care is taken 
with it. 
CONTINENTAL GARDENS. 
[The following particulars are translated 
from an account of a horticultural tour, 
published by M. Lecoq : — ] 
Leybach, the ancient capital of Illyria, 
stands on the very banks of the Leybach, a 
noble river which runs through a piece of 
water apparently at one time a lake. There 
are some fine promenades at this place, but 
not to be compared to those which are' 
met almost in every town of Germany ; here 
grafted rose trees are frequently to be seen 
attaining upwards of thirty feet ; and it is 
not rare to find the eglantine reaching to 
the second story of the houses to which 
it is trained. 
VIENNA. 
Vienna is surrounded by a fertile and smil- 
ing landscape, watered by a small river from 
which its name is derived. 
The Botanic garden, which is very ex- 
tensive, and well laid out, is one of the most 
remarkable. The plants are arranged according 
to their natural orders, and grouped according 
to their affinities ; representing the graphic 
classification which is to be sometimes seen on 
paper ; while the analogies and points of re- 
semblance are preserved as much as possible. 
A great part is laid out in clumps, having 
trees in the centre, and shrubs and herbaceous 
plants converging to the margins. 
Each genus with its species is placed in a 
separate clump, which is generally made large 
enough to admit additions that may be made 
from time to time to the collection of plants. 
By this arrangement the plants are in the 
most natural position to be properly studied. 
This plan is not, however, only carried out at 
Vienna ; it is adopted at Edinburgh, and 
some years ago. Professor Morren put it in 
practice at Liege. The extent of the Botanic 
Garden at Vienna gives this arrangement a 
decided advantage. 
Extensive houses and arboretums, a ca- 
pacious lecture-room and an herbarium, are 
among the principal objects ; some rustic 
houses formed of the trunks of birch trees, 
here and there, have a very fine effect. To 
these erections the Cobcea scandens is trained, 
x2 
