390 
THE GARDENING!- WORLD, 
Feb. 21st, 1885. 
beautifully the whole form of these leaves was 
adapted to the mode of growth and arrangement of 
the buds in the plants themselves. In the Black 
Poplar the arrangement of the leaves was again quite 
different. The leaf-stalk was flattened, so that the 
leaves hung vertically. It would be observed that, 
while in most leaves the upper and under surfaces 
were quite unlike, in the Black Poplar, on the 
contrary, they were very similar. The stomata, or 
breathing-holes, moreover, w r hich in the leaves of 
most trees were confined to the under surface, were in 
this species nearly equally numerous on both. 
The Compass plant of the American prairies, a 
yellow composite not unlike a small Sunflower, was 
another plant with upright leaves, which, growing 
in the wide open prairies, tended to point north and 
south, thus exposing both surfaces equally to the light 
and heat. It was shown by diagrams that this position 
also affected the internal structure of the leaf. In the 
Yew the leaves were inserted close to one another, 
and were long and linear, while in the Box they were 
further apart and broader. In the Scotch Fir the 
leaves were linear, and li ins. long; while in other 
Pines, the Weymouth, for instance, the stem was 
thicker and the leaves longer. In the plants hitherto 
mentioned one main consideration appeared to be the 
securing of as much light as possible ; but in tropical 
countries the sun was often too powerful, and the 
leaves, far from courting, avoided the light. The 
typical Acacias had pinnate leaves, but in most 
Australian species the true leaves were replaced by 
a vertically flattened leaf-stalk. It would be found, 
however, that the seedlings had leaves of the form 
typical in the genus. Gradually, however, the leaf 
became smaller and smaller, until nothing was left 
but the flattened leaf-stalk or phyllode. In one species 
the plant throughout life produced both leaves and 
phyllodes, which gave it a very curious and interesting 
appearance. In Eucalyptus, again, the young plant 
had horizontal leaves, which in older ones were 
replaced by scimetar-shaped phyllodes. Hence the 
different appearance of the young and old trees which 
must have struck every visitor to Algiers or the 
Bi viera. 
So much for deciduous trees. In evergreens the 
conditions were in many respects different. It was 
generally said that leaves dropped off in the autumn 
because they died. This, however, was not strictly 
correct. The fall of the leaf was a vital process, 
connected with a change in the cellular tissue at the 
base of the leaf-stalk. If the leaves were killed too 
soon they did not drop off. The lecturer illustrated 
this by some twigs which he had purposely broken in 
the summer; below the fracture the leaves had been 
thrown off, above they still adhered, and so tightly 
that they could support a considerable weight. In 
evergreen trees the conditions were in many respects 
very different. It was generally supposed that the 
leaves lasted one complete year. Many of them, 
however, attained a much greater age ; in the Scotch 
Fir three or four years; in the Spruce or Silver, six 
or seven ; in the Yew, even longer. It followed from 
this that they required a tougher and more leathery 
texture. 
When we had an early fall of snow our de¬ 
ciduous trees were often much broken down; glossy 
leaves had a tendency to throw it off and thus 
escape; hence evergreen leaves were very generally 
smooth and glossy. Again, evergreen leaves often 
had special protection, either in an astringent or 
aromatic taste, which rendered them more or less 
inedible, or by thorns and spines. Of this the Holly 
was a familiar illustration, and it was pointed out that 
in old plants, above the range of browsing quadrupeds, 
the leaves tended to lose their spines and become 
unarmed. The hair on leaves were another protec¬ 
tion. On herbs the presence of hairs was often 
associated with that of honey, as they protected the 
plants from the visits of creeping insects. Hence, 
perhaps, the tendency of water species to become 
glabrous, Polygonum amphibium being a very 
interesting case, since it was hairy when growing on 
land, and smooth when in water. 
The lecturer then dealt with cases in which one 
species might be said to mimic another, and he 
exhibited a striking photograph of a group of Stinging 
Nettles and Dead Nettles, which were so much alike 
as to be hardly distinguishable. No one could doubt 
that the Stinging Nettle was protected by its 
poisonous hairs, and it was equally clear that the 
innocuous Dead Nettle must profit by its similarity to 
its dangerous neighbour. Other similar cases were 
cited. Beference was next made to aquatic plants, 
many of which had two kinds of leaves, one more or 
less rounded which floated on the surface, and others 
cut up into narrow filaments, which remained below. 
The latter thus presented a greater extent of surface. 
In air, however, such leaves would be unable to 
support even their own weight, much less to resist 
any force such as that of the wind. But in perfectly 
still air, for the same reason, finely divided leaves 
might be an advantage, while in comparatively 
exposed situations more compact leaves might be more 
suitable. It was pointed out that finely-cut leaves 
were common among low herbs, and that some families 
which among the low and herb-like species had such 
leaves, in shrubbery or ligneous ones had leaves more 
or less like those of the Laurel or Beech. 
An interesting part of the subject was connected 
with the light thrown by the leaves of seedlings. 
Thus the Furze had at first trifoliate leaves, which 
gradually passed into spines. This showed that the 
Furze was descended from ancestors which had 
trifoliate leaves as so many of its congeners had now. 
Similarly, in some species, which, when mature, 
had palmate leaves, those of the seedling were heart- 
shaped. Perhaps, in all cases the palmate form was 
derived from the heart-shaped, and when in any 
genus we found heart-shaped and lobed-leaves, the 
former might represent the earlier or ancestral 
condition. 
If there was some definite form told off for each 
species, then surely a similar rule ought to hold 
good for each genus. The species of a genus might 
well differ more from one another than the varieties 
of any particular species ; the generic type might be, 
so to say, less closely limited ; but still there ought to 
be some type characteristic of the genus. One genus 
was that of Senecio (the Groundsel). In addition to 
Senecios more or less resembling the common 
Groundsel, there were species 'with leaves like the 
Daisy, bushy species with leaves like the Privet and 
the Box, small trees with leaves like the Laurel and 
the Poplar, climbing species like the Bryony. In 
fact, the list was a very long one, and showed that 
there was no definite type of leaf, but that the form 
in the various species depended on the condition of 
the species. 
From these and other considerations, the lecturer 
concluded that the forms of leaves did not depend 
on any inherent tendency, but to the structure and 
organization, the habits and requirements of the 
plant. Of course, it might be that the present form 
had reference to former, and not to present, conditions, 
This rendered the problem all the more complex and 
difficult. The subject presented a very wide and 
interesting field of study, for if he were correct in his 
contention, every one of the almost infinite forms of 
leaves must have some cause and explanation. 
- e.- - 
A NEW RAFFLESIA. 
Under the name of Bafflesia Schadenbergiana, a 
new species is figured in the January numberiof the 
Gartenflora. It was found growing in Mindanao, an 
island of the Philippine group. The flower measures 
6 ins. to 8 ins. in diameter, and the colour is a warm 
brown, with numerous yellow markings. This makes 
the fifth known species of this remarkable genus, all 
of which grow parasitically on the roots and lower 
portions of the stems of certain vines, without the 
slightest apology for a leaf. The most remarkable 
species, B. Arnoldii, has a flower from 2 ft. 6 in. to 3 ft. 
in diameter, a size perhaps unrivalled in the whole 
vegetable kingdom. B. Patma, from a small island 
on the coast of Java, measures 1 ft. 6 in. to 2 ft; B. 
Bochussenii, from Java, is 6 ins. in diameter ; and B. 
Cumingii, another Philippine species, is of the same 
size. 
The original species, B. Arnoldii, was discovered in 
forests in the interior of Sumatra, by Sir Stamford 
Baffles and Mr. Arnold, and specimens were sent to 
England in 1818. Mr. Arnold observes that when on 
his travels, his native servant appeared with the 
words, “ Come with me, sir, come! a flower, very 
large, beautiful, wonderful 1 ” Mr. Arnold went and 
saw the flower, a yard in diameter, and weighing 
12 lbs. to 15 lbs. He further remarks, “Had I been 
alone, and had there been no witnesses, I should, I 
think, have been fearful of mentioning the dimensions 
of this flower, so much does it exceed every flower I 
have ever seen or heard of.” The cup of the flower 
is said to be capable of holding twelve pints of water. 
No doubt many of our readers have seen the wax 
model, life size, of this flower, in the Museum at 
Few. 
- 'J—" 'TZ _ 0 
IMPROVING A LAWN. 
It would have been much more easy to give a 
satisfactory reply to “A New Subscriber” (see 
p. 382) had he stated whether the lawn in question 
was located in town or country. In smoky districts 
lawns will become debilitated in a few years, and the 
best way of renovating them under such circum¬ 
stances is to take up the old and replace it with 
new turf. If the grass has been worn off by over 
much playing on it, and the grass quite killed in 
places, the best plan is to take up those patches where 
the grass is quite dead, and replace it with some good 
turves from an old pasture. It may look rough for a 
time, but when cut in April when the grass begins to 
grow it will soon come round. The laying of the turf 
should be done at once, so that the roots of the grass 
may get a hold before dry weather sets in. If the 
grass is only thin in places, probably the best plan 
is to sow seeds, but this should never be done before 
the beginning of April, for though grass is hardy 
enough when established, the young blades as they 
break from the seed are very tender at first, and a 
sharp frost would check them for a length of time, if 
it did not even destroy them. 
Probably the best way to proceed with a lawn where 
the grass is thin is to rake it hard with a sharp and 
rather long-toothed rake, so as to make a loose 
bed for the seed to lie upon, and this will not destroy 
the grass already there. A little fine soil may be 
added at the same time to make the lawn perfectly 
level. The seeds should be sown rather thickly if it 
is desirable to have the lawn covered soon; the rake 
should then be drawn over it so as to mix the seed 
and the soil a little, but not by any means to draw 
anything in front of the rake. All that is necessary 
then is to pass a garden-roller over it, but should the 
weather be very dry it must be watered, assuming 
that it is wanted green as early as possible; if the 
weather is showery it will not be necessary. If any 
part of the lawn is mossy, dress it with a mixture of 
very fine cinder ashes with a spr inklin g of soot and 
slaked lime, say four parts of the former to one of the 
two latter. Grass seed such as is sold by respectable 
seedsmen as “Lawn Grass Seed” would suite “A 
New Subscriber’s ” purpose well. After the seed has 
come up sufficiently high for cutting it should be mown 
with the scythe for the first time or two and be rolled, 
after which the mowing machine is the best, as that 
both mows and rolls the grass at the same time.— 
C. Warden. 
Your correspondent, “ A New Subscriber,” does 
not state what are the surroundings and drawbacks to 
his lawn, or whether it is much over-hung, hard- 
trodden, or simply bare from poverty of soil, sub¬ 
soil, or want of proper attention. Presuming the 
latter, I would advise him to give it at once a good 
dressing of salt and soot, and in the meantime to 
make up a heap of compost consisting of two parts of 
fresh turfy soil and one part of very rotten manure. 
He must work this over and over till it is all quite 
fine and well broken up, and if not fine enough may 
run it through a i-in. riddle. By about the end of 
March he should have ready a mixture of lawn grass 
seeds, which he can buy ready mixed at the seed 
warehouses; or he may mix them himself. If he 
prefers to mix them himself, he must ask for Festuca 
ovina (the meadow fescue), Festuca tenuifolia (fine¬ 
leaved fescue), and Poa pratensis (the smooth-stalked 
meadow grass). If at all shaded with trees he may 
use instead of the latter Poa nemoralis (the wood 
meadow grass). A mixed quart of these will sow a 
very large plot of lawn, only one bushel being 
generally used to an acre in renewing old pastures or 
lawns. 
It will be advisable to go over the whole of the 
lawn with the seed, but to sow thickest where the 
lawn is most bare. Now spread over all the heap of 
compost, making a thickness of from one half to one 
