February 25, 1893. 
THE GARDENING WORLD. 
407 
carbonic acid gas and liberating oxygen. In this 
way they kept the air in the glass globe continually 
pure. 
It was important, he said, to emphasize that 
plants and animals were, in regard to breathing i 
precisely the same. Supposing they had in a room 
at night a dog, a plant, and a lighted candle—all of 
them were oxidising complex organic substances, 
and all of them were taking oxygen out of the air 
and returning carbonic acid gas to it ; there was no 
essential difference in the respiration of the plant 
and the animal—the result was the same and for a 
similar reason. This was one of the most funda¬ 
mental inter-relations between animal and plant 
life : that plants and animals breathe, though green 
plants during the day have an extra power which 
was the reverse of respiration, and which, during 
the day, masks the respiratory process. Many 
animals fed upon plants, and all animal life in the 
long run depended upon the life of plants; but, 
while plants were able to live on inorganic matter, 
animals—except a few known ones—were unable to 
feed at such a low chemical level, and so had to 
depend upon the plants. Now, he said, plants being 
passive organisms, were unable to retaliate, the only 
approach to it on the part of animals being those 
parasitic plants which destroyed animals, and the 
insectivorous or carnivorous plants. 
These latter were a large physiological assemblage, 
there being no less than 500 species, all of which 
were to be found in most parts of the world. The 
pitcher-plants (Nepenthes) had their headquarters 
in Borneo and other Indian Archipelago Islands. 
Venus’s Fly-trap was limited to Carolina in the 
United States. Yet they were represented in most parts 
of the world. He would, however, take the British 
form of these plants, which was less familar than 
others. Growing in thick woods, often by Ivy at the 
foot of a tree, there was a weird bell-plant called the 
Toothwort (Lathraea) ; and those who found it were 
not at all likely to forget it. It was a strange plant, 
rare in this country, and it was one of those plants 
which had no green colouring matter, but was de¬ 
pendent for its food upon the organic matter manu¬ 
factured by other plants. It preyed upon the roots 
of the tree near which it grew ; and it was perhaps 
the simplest example of the carnivorous plant. Then 
there was the Butterwort, which they saw every¬ 
where in boggy ground. The leaves were glistening, 
and were covered with numerous glands—25,000 to 
a square centimetre. There was a viscid secretion, 
like insect lime, on the leaf. The leaf turned in¬ 
wards, and digested its food. That was a step in 
advance, because the Toothwort simply decomposed. 
Then there was the common Bladderwort (Utri- 
cularia) which grew in our lochs and was exceedingly 
beautiful in the month of July or August. This was 
an insectivorous plant, widely distributed over the 
earth. It was a plant without roots, having got a 
floating stem ; and some of its numerous leaves were 
modified into little bladders, which were effective 
traps for small animals—not for insects, because few 
of these were acquatic, but for small crustaceans, 
such as water fleas and copepods. One could hardly 
tell why such creatures would trouble these litt'.e 
traps; but, as there was a sweet mucillage at the 
mouth of the trap, he thought it was likely these 
small crustaceans ventured too far, or were pressed 
by their enemies. Once they were in no amount of 
pressing from the inside would enable them to get 
out; and as many as twenty-four of these small 
animals had been got in one bladder. They soon 
died, because there was no fresh air; and then they 
decomposed and were absorbed. The Nepenthes, or 
Pitcher Plant, had a peculiar leaf which was a very 
effective trap for insects. The lower half of it was 
full of water with organic juice in it and from its 
bath insects rarely escaped. In other pitchers, 
such as Sarracenia—from which they could often 
get fifty insects—there was no water ; but the lower 
part of the pitcher was lined with hard, stiff, long 
hairs, down which it was easy for an insect to creep, 
but up which it was as impossible for an insect to go 
as it would be for a man to make way against a 
hedge of steel spears. 
Then, again, there was the Venus’s Fly-trap, which 
Linnaeus, 150 years ago, called “ the miracle of 
nature.” The peculiarity of this sensitive plant was 
that on either side of the leaf there were three very 
fine hairs, and if an insect knocked against one of 
these, the leaf immediately closed, and escape was 
qopeless. In these insectivorous plants there was 
nothing, however, that was not in any other plant, 
there was only a more perfect digestion. The Sun¬ 
dew was an instance where the leaves closed, like a 
fist, upon any insect that got entangled in one of its 
hairs or tentacles ; yet in spite of this delicacy the 
plant gave no response to a raindrop or friction with 
a piece of grass growing near. They would thus see 
there was in this plant something like the power of 
discrimination, though not so appreciable as in 
animals or mankind. The reason of this peculiarity 
in some plants was that they must have nitrogenous 
salts; and, if the plants which he had enumerated 
had not their proper sh ire, they made up for it by 
catching insects. It was, therefore, of some real ad¬ 
vantage to them to catch these insects, because it 
was from them that the plants got the nutritive salts 
which was part of their living material. The lecturer 
then asked their attention to the question of honey- 
dew. 
It was well known, he said, that on many trees 
there was a sweet viscid secretion, so abundant in 
some cases that in an avenue of limes the pavement 
was often wet with the drops of honey-dew which 
fell from above. This honey-dew had been known 
through all ages. Pliny discussed it in detail, and 
wondered whether it was distillation or an exudation 
from the air; but he came to the conclusion that it 
fell like dew from above. Darwin also considered 
it an exudation, but from the plant itself. Dr. 
Biisgen’s conclusion was that the honey-dew was 
produced slowly by the little plant lice ; that it was 
an exudation not of the plant but of plant life. This 
was based upon (1) that the drops seen on the leaf 
had no connection whatever with the structure of the 
leaf, because they appeared on the dry withered 
parts ; (2) that the drops were seen at first singly, 
and never grew bigger except by coalesence with 
their neighbours ; (3) that honey-dew was never seen 
upon a plant unless visited by Aphides ; an Aphis 
could discharge fifteen drops of honey-dew in a day 
and when it was considered there were several thou¬ 
sand Aphides on a Lime tree they could understand 
the juice being large enough to drop on the pavement 
beneath. This honey-dew brought a benefit to the 
plant. It was much liked by ants ; and as ants on 
the whole, were favourable to plant life, though some 
of them were mischievous, they helped to ward off 
more injurious insects from the plant. 
It was interesting to notice how plants were, in 
manifold ways, preserved from being eaten up by 
animals. There was one cause which he should 
like to discuss; that concerning the relations 
between snails and plants. There were two kinds of 
snails—omnivorous and specialists (laughter). 
The latter were very dainty in their diet, and did 
not like to eat anything but Mushrooms. The 
majority, however, were omnivorous, and they were 
not fastidious (laughter). They heard much about 
the relations of insects and plants, but the relations 
between snails and plants were of an entirely different 
character. Snails, although they were,not fastidious, 
drew the line somewhere. There were certain 
plants which they always eschewed, and it was 
interesting to inquire into the reason why they did 
avoid certain plants. The impulse of hunger might 
occasionally force them to make experiments on the 
plants they usually avoided, but they either died as 
the result of the research and left their shells as 
warnings, or they detected the taste in time and left 
the plant in disgust. This was such a problem that a 
true German would attempt—to find out what was 
the favourite menu of the snails, and make a theory 
of it. 
Professor Stahl had found out 15 different ways 
in which plants were abhorrent to snails, and were 
thereby protected. Some plants were too sour, 
others were poisonous, some were full of ferments, 
and on others there were hairs that pricked the soles 
of the snails’ feet (laughter). This research of 
Professor Stahl was very valuable, but he (the 
lecturer) joined issue with him when he said the 
snails were responsible for the sourness of certain 
plants. He maintained that the acids and the fer¬ 
ments which were found in the plants were con¬ 
stitutionally part and parcel of the plants. Dealing 
next with bacteria, he said that this completed the 
circle between animal and plant life—the plant fed 
on the inorganic, the animal fed on the plant, 
the animal died, and bacteria reduced that animal’s 
corpse to pure elements. That was one of the most 
fundamental and important parts played by bacteria 
in the drama of Nature. 
Gardening Miscellany. 
Cjb 
FREESIAS AND WHITE ITALIAN HYACINTHS. 
Freesias are so often shown in an emaciated, sickly 
condition on the conservatory stage, that they are 
not so much grown as they might and ought to be. 
When they are well done they repay the grower 
twice over. About the best I have ever seen were a 
batch I came across the other day at Bystock, near 
Exmouth, the seat of J. P. Bryce, Esq , where Mr. 
W. Swan now finds a field for his capabilities in 
some respects. Grown in 5-in. pots, with 8 to 10 
bulbs in a pot, they were perfect pictures of suc¬ 
cessful cultivation. The foliage was vigorous, stiff, 
and of a good colour, and the trusses of bloom were 
numerous, full of pips from the middle to the end of 
the stalk, each pip large and well developed. I be¬ 
lieve half the battle in growing Freesias to perfection 
is to plant them early. Keep them well drained 
that the bulbs may never rest in a saturated soil, and 
have the compost underneath richer in substance 
than the bed in which the bulbs sit. I was so struck 
with the evidence of skill in the cultivation that I 
forgot to ask Mr. Swan as to his treatment of them. 
Another thing he had in absolute perfection was a 
batch of white Italian Hyacinths. These are most 
valuable to succeed the Romans, as they come in a 
fortnight later at least. The trusses are stronger, 
the pips more plentiful, and altogether superior to 
the early white Roman. Many of the spikes had 
16 and 18 pips on them, and bore themselves proudly. 
They were, indeed, the best I ever saw, and although 
this variety of the Hyacinth has merits that have 
for long been overlooked, the plants bore abundant 
evidence of skill in cultivation.— A. H. 
THE CURRANT-BUD MITE. 
The following advice is given by the Board of Agri¬ 
culture:—When Black Currant bushes are planted 
theyshould be carefullyexamined forPhytoptus Ribis. 
If there are any signs of unnaturally swollen buds the 
young bush should not be planted. In taking 
cuttings in the late autumn, those from infested 
bushes must be rejected absolutely. Infestation is 
easily seen then by the abnormal buds. Infested 
bushes should be cut very hard, and every particle 
of the cuttings carried away and burnt. In the 
spring the bushes should be syringed well all over 
with a solution composed of 1 ounce of paris green 
to from 11 to 12 gallons of water, with 2 ounces of 
fine wheat flour added, or 2 ounces of soft soap, to 
make the solution adhere better. The Eclair " Knap¬ 
sack ” pump may be employed for this, and it must 
be impressed upon the labourers to direct the spray 
over every part of the Currant bushes. Another 
solution for spraying, to be used in a similar manner, 
may be composed of 5 to 6 lbs. of soft soap, mixed 
with the extract of 8 or 9 lbs. of quassia chips, to 
100 gallons of water ; 3 quarts of carbolic acid might 
be substituted for the quassia. Spraying with these 
solutions should be repeated in the autumn before 
the weather becomes cold, and just after the leaves 
have fallen, if possible. This will economise liquid 
and labour, and will affect the mites before they get 
into the buds. Directly the leaves have fallen, it 
would be desirable to put hot lime round the stocks 
and dig it in at once, so as to bury the leaves with 
any mites that may be upon them, and thus prevent 
any chance of their getting up the stems. In very 
bad cases it would pay to cut the bushes close to the 
ground, and in the autumn and early spring to 
syringe the stocks with the paris green solution, or 
the carbolic acid solution. This would entail the 
less of one year’s crop only. 
DAVIDSONIA PRURIENS IN FRUIT. 
The value of this Australian plant is as an orna¬ 
mental-leaved stove subject. The long, hairy 
pinnate leaves are imposing at all times of the year, 
but in particular in spring and the early part of 
summer, when the hairs covering the young and 
half-developed leaves are of a bright, velvety, 
crimson-red, reminding us of the fruit of Rhustyphina 
in September and October. Just when the leaves 
are half developed the red hairs are closely crowded 
together, and give that magnificent effect for which 
the leaves are notable when making their growth. 
Flowers have frequently been produced in the stove 
and Palm house at Kew, but fruits are seldom pro¬ 
duced. At present, however, a fruit may be seen in 
