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Curtis's Botanical Magazine/Volume 63/3500

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135932Curtis's Botanical Magazine, Volume LXIII — 3500 Dryandra pteridifolia.William Jackson Hooker



[ 3500 ]


Dryandra pteridifolia. Fern-leaved
Dryandra.

***************
Class and Order.

Tetandria Monogynia.

(Nat. Ord. - Proteaceæ)

Generic Character.

Perianthium quadripartitum vel quadrifidum. Stamina
apicibus concavis laciniarum immersa. Squamulæ hypo-
gonæ 4. Ovarium uniloculare biovulatum. Ovula post
fæcundationem cohærentia. Folliculus ligneus.Disepimentum ligneum semibifidum frûctus maturi omninò simile.
Receptaculum commune planum, floribus indeterminatim
confertis; paleis angustis, rarò nullis. Involucrum commune imbricatum.-Frutices plerumque humiles. Rami dum
adsint sparsi vel umbellati. Folia sparsa, pinnatifida v.
incisa, plantæ juvenilis conformia. Involucra solitaria, ter-
minalia, rarò lateralia, sessilia, foliis confertis, interioribus
quandoque nanis obvallata, hemisphærica, bracteis adpressis,
in quibusdam apice appendiculatis. Stylus sæpè perianthio
vix longior. Br.

Specific Character and Synonyms.

( �§. Aphragma. )

Dryandra pteridifolia; foliis pinnatifidis caule abbreviato
erectiusculo, vel propensè decumbente tomentoso lon-
gioribus : lobis elongato-linearibus acutis, s. oblongo-
linearibus obtusis mucronatis, margine revolutis, peri-
anthii laminis colorato-lanatis apice penicillatis, invo-
lucri squamis exterioribus lato-ovatis spadiceo-tomen-
tosis.
(α) lobis foliorum obsoletè nervosis basi dilatatis, caule
erectiusculo. (Tab. nostr. 3500.)
DRYANDRA
VOL. X. H
--

Dryandra pteridifolia. Brown in Linn. trans. v. 10. p.
215. Ejusd. Prodr. v. 1. p. 399. Röm. et Schult.
Syst. Veget. v. 3. p. 447.
(β.) lobis foliorum manifestè trinervibus, basi simplici,
caule perquam humili, ramis floriferis præsertim pros-
tratis.
DRYANDRA blechnifolia. Br. in Linn. trans. et Prodr.
necnon. Röm. et Schult. Syst. Veget. in locis citatis.







When Mr. Brown published the first volume of his invaluable Pro-
dromus, the plant here figured, which was discovered by that very
eminent Botanist on rocky hills, at King George's Sound, was regarded
by him as possibly a distinct species from another named D. blechni-
folia, of which specimens without fructification, and originally gathered
also on the shores of the Sound, by our highly respected and venerable
friend Mr Menzies, in his voyage with Vancouver, were preserved
Banksian Herbarium. A subsequent examination however, of
more perfect specimens, has proved them to be but varieties of one spe-
cies differing from each other chiefly in habit, and in some measure in
the figure of the lobes of the leaves, although in some native specimens
examined, there is manifestly a disposition to produce the two shapes of
leaves upon the same plant.

The present remarkable and variable subject was raised from seeds,
collected by the late very indefatigable botanic-voyager, Mr.W. Baxter,
during his first visit to the South-western shores of Australia, in 1823;
and the specimens transmitted us from Kew, by the liberality of Mr.
Aiton, last spring, were taken from a plant, which we understand, is
not only the first that has produced flowers in Britain, but is the only
example of the species at this time alive in Europe. It may here be
added at for its presence at all in our collections, as indeed for the
introduction to England, of many others of the rarer and more beauteous
of Australian vegetables, cultivators of ornamental exotic plants are en-
tirely indebted to the disinterested liberality of F. Henchman, Esq.

Descr. Our plant in cultivation exhibits the contour of a dwarf,
bushy shrub, with short, flexuose branches, clothed with a whitish wool.
Leaves exceedingly rigid, crowded, and pinnatifid; lobes alternate, for the
most part linear, an inch and a half to two inches long, terminated by a
sharp, rigid mucro, the margins revolute, base dilated, covered on the
under side with a ferruginous tomentum and nerved, the nerves even-
tually obsolete; upper paginæ of a very dark green and glossy. Flowers
in terminal heads, surrounded by coloured leaves, of a faint honey-scent.
Involucre closely imbricated, clothed with a very dense reddish-brown
tomentum, having the outer bractes elliptical, acuminate, very smooth
within, and the inner scales linear, covered with orange-coloured appress-
ed, rigid hairs, pencilled at the apex. Perianth deeply divided into
four equal segments, invested with a pink-coloured, curled wool, barer
towards the base : lamina linear, much longer than the unguis, tipped
with a pencil-like tuft of soft, spreading hars. Stamens four, inserted
in the long, concave extremities of the laminæ. Anthers linear, apicu-
lated
--

lated, bursting longitudinally. Style terete, obscurely sulcated, exserted,
longer than the perianth, very smooth, slighttly subulate, thickened
towards the base. Stigma simple. Hypogynous glands four, oblong,
bilobed.




The eager avidity with which spirited, liberal-minded gentlemen in this
country, have, at various periods in the course of the last forty years, sought
to possess and maintain in their collections living examples of the many
Genera of Proteaceæ, affords an abundant proof of the great interest
they have excited, and of the high estimation in which plants of a family,
possessing forms no less extraordinary than numerous, whether indigenous
to the Cape of Good Hope, or to the arid shores of Australia, have been held.

At one period, within, doubtless the recollection of some of our readers,
not only the King's gardens at Kew, and the rich Conservatories of George
Hibbert, Esq. at Clapham, but the gardens of other gentlemen,and espe
cially the sale-collections of the more eminent nurserymen around London,
could boast of many choice specimens of Cape Proteaceous plants, which
in the present day, are nowhere to be seen; for having been urged by cuture
to put forth their showy flowers, they immediately afterwards, in many in-
stances, exhibited, from some mistreatment, debility and sickness, and
eventually dying, have ever since been lost to Britain. Since an ignorance
at the time, of the proper mode of managing the plants of this family, whether
natives of the Cape or of New Holland, doubtless led to the mortality that
prevailed at periods not many years subsequent to their having been raised
from the imported seeds, perhaps it may not be out of place in this work, to
give our readers the substance of a few practical observations offered us, on
the successful treatment of certain of the Order, as pursued at Kew by the
principal very able cultivator in that garden, Mr. John Smith, to whose
horticultural knowledge is superadded a critical botanical discriminiation of
plants generally, and especially of that numerous and beautiful tribe, the
Filices, and to whose talents in these particulars, we are happy, in common
with other Botanists in Britain and on the continent, especially attached to
the study of Cryptogamic vegetation, to bear ample testimony.

Adverting to the interesting pamphlet of Mr. Macnab, the excellent
Superintendent of the Royal Botanic Garden at Edinburgh, on the propaga-
tion and culture of Cape Heaths, which appeared in 1831, Mr. Smith
observes, that he had pursued with success for some time antecedent to that
date, the same mode of treatment of Proteaceæ under his care, that is re-
commended in that publication, with respect to the culture of Heaths, viz.
in regard to shifting the plants into fresh and larger pots; in the process of
which, it is very important to afford, by means of potsherds, or fragments of
half-baked pottery, a good drainage below, and especially to avoid deep pot-
ting, by placing the plant, with its ball of earth round the roots quite entire,
so as to be some two or three inches above the surface of the soil at the edge
of the pot, which will have the effect of carrying off any superabundant
moisture from the roots to the circumference, and thus prevent the chance of
water becoming stagnant round the base of the stem; by inattention to this
latter circumstance, many a Banksia and Dryandra in other collections
have been killed; whilst a steady regard to free drainage, to an abundant
circulation of air, and a low temperature, he has succeeded in preserving
many fine proteaceous plants longer than is generally effected in other gar-
dens in the neighbourhood of London.

"Even in the present day," he observes, "there may be some few
gardeners, who may object to the mode of potting certain plants here insisted
on, on the ground that, by being thus raised in their pots above the soil at
the edge, they have not a handsome look; and this practice, now adopted and
recommended
--

recommended by Mr. Macnab with regard to Cape Heaths, &c., had its
prejudice on his mind for years, for no other reason, as he himself tells us,
"than that I fancied the plant looked as if it were ill potted, and, to my
view, unsightly." " But we now see, how much other and more judicious
management, founded on physiological principles, has overcome the preju-
dices of former days, and the difficulties attendant on the culture of not
simply these, but the plants of other tribes:-witness our orchideous Epi-
phytes.

"The soil," continues this intelligent cultivator, "which I use in the cul-
tre of most of the Proteaceæ, is a good fresh loam, with which, if stiff,
I mix a portion of sand, so as not to admit of its being retentive of water.
In time, after being potted as already directed, the main roots next the stem
of the plant will become uncovered: this circumstance I regard as favour-
able to the health of the plant: there will be no danger of its dying suddenly,
as I have known many to do, that have been buried alive,–in other words,
been deeply potted!"

"In the winter months, care should be taken not to saturate the earth with
water, nor wet the leaves or stem more, than can be avoided. In dry weather
however, during the summer season, water may be freely given to the plants
about sunset, and a very essential point to be observed is, that, when they
are placed out in the open air in groups, the sun's rays should not be
allowd to fall directly on the sides of the pots, for if they are, all the feeding
spongioles of the tender roots round the inner side of the pot, will assuredly
be destroyed, and the life of the plant greatly endangered. Repeatedly have
I known a Banksia to have been killed by the solar ray having been thus
allowed to act on the side of the pot, which six months' afterwards retained
so much of a life-like look–being kept yet in its pot–as to appear to the
eye of a superficial observer, to be still alive, and in perfect vigour. The
lowest greenhouse-temperature that can judiciously be allowed, to prevent
the effects of frost, is sufficient for the generality of the family now in culti-
vation in Britain, and no artificial heat is required for their preservation,
excepting in severe frosty weather." He adds, with reference to pruning,
that "as the rapid upright-growing species are, if left to themselves, shorter-
lived, than others naturally more robust, the free use of the knife is recom-
mended the growth of the plants checked, by keeping the luxuriant
shoots cut back. This remark is especially applicable to those beautiful
plants of the Order, with simple, straight, wand-like stems, such for example
as Banksia Brownii and Dryandra Serra, Br., the former of which
has been lost to several collections that could once have boasted of it, by its
having been suffered to shoot up into exuberant growth, far beyond what
the slender, tapering, thinly-fibred root could at all furnish sustenance.
By heading these down somewhat, and thus reducing the ascending axis,
or column of circulation, a more robust habit is induced, a growth of roots
in their pots takes place, lateral branches are thrown out, and the plants thus
treated at Kew, are now in the best possible health, with every indicative of
being fully established in that garden".
To the above observations of an intelligent and practical man, may be added
a few very brief remarks on the habits, economy, and indispensable treat-
ment, in cultivation, of a division of Australian Proteaceæ, growing natu-
rally on the sea coasts, or upon barren tracts within the influence of the sea
air, in the tropical regions of that continent. The Genera hitherto observed
on the equinoctial shores of New Holland are Grevillea, Hakea, Per-
soonia, Stenocarpus,
and Banksia, and these comprise a group collec-
tively of thirty-three species, of peculiar constitution entirely governed in
their growth, and general development, by the circumstances and modifica-
tions of the climate in which they exist.

It is a well-known fact, that what constitutes the change of season in
intertropical
--

intertropical regions is not any approach to the winter of countries within
the temperate sones, much less of those of the higher latitudes, in respect to
any material difference of atmospheric temperature at opposite periods of the
year, but (we are speaking of the climate of the sea coast) is due to that
periodical, well-defined break-up, from great drought to extreme humidity,
commonly called the dry and rainy seasons. With such perfect regula-
rity do these changes of season take place on the N. W. coast, that our friend
Capt. P. King R. N., who was employed, during nearly five on its
survey , could l forward almost to the very day when the break-up
easterly monsoon, and with it the period of drought, would obige him
peremptorily to stand off shore, and immediately to quit the coast. It was
during the existence of that monsoon, which prevals between May and
October, when the wind blows steadily off shore, that portions of that survey
were annually conducted, and the Botanist of the voyage, although he landed
almost daily from the vessel to pursue his researches, 'twas oftentimes but to
behold vegetable life in a state of extreme langour, by the aridity of the
atmosphere, and its uniformly high fervid temperature.
The Graminee, and, indeed, herbaceous plants generally, had suffered
in the early part of the season : these were all burnt up, and the more woody
vegetables, the shrubs, arbusculæ, and stunted timber trees bore the marked
evidences of participation in the general distress. None were detected in a
flowering state, whilst all were laden with their ripened fruits. The Acacias,
of which every sandy beach and rocky islet furnished some species, bore
their clustered pods on branches, in many species incrusted with a
brittle concrete matter, that had exuded through the cuticle, which ap-
peared by thus covering the bark, the phyllodia, and buds, to suspend for
a time, the operation of their respective functions, and thus lull vegetable
life into a state of quiescence. All nature wore an air of desolation, and the
vegetable world assumed an aspect unusually gray and gloomy. But it was
its season of rest-that period of repose which appears essential to vegetation
generally in tropical countries, to enable it upon the return of the rains, to
burst forth with a renovated strength into fresh life, and undergo with vigour
that sudden and prodigious development of leaves and flowers, which con-
stitutes the beauty and grandeur of the vegetables of warm countries.

During the surveys of Capt. King just noticed, the seeds of no less than
twelve species of Proteaceous plants, (and chiefly of Mr. Brown's last
section of the Genus Grevillea,) were received at Kew. Plants of each
were readily raised, which afterwards, with the treatment they received, grew
to the stature of large shrubs, and some eventually flowered, to the admira-
tion of all visitors.. But these goodly plants were not destined to long life in
the Kng'sgardens, for, inattentive to the conditions under which alone, those
lovelier forms of Australian vegetation exist on their native coasts, they were
urged immediately after flowering, into a new and unnatural vigorous growth.
In vain they looked for some short season of rest, by perhaps a dryer
warmth, with but the slightest possible watering afforded, to sustain life–a
treatment, to which their constitutions, inherited from their parents, ap-
peared so fully adapted. They found none; but debility resulting from
forced culture, was followed by extreme exhaustion, and death closed the
scene! But we have yet to discover, in our future endeavours to cultivate
the shrubby vegetables of the sands of the intertropical shores of that vast
country, by what mode of treatment, plants delighting in a high atmospheric
temperature, and subject to the extremes of drought and humidity at oppo-
site periods of the year, can possibly be cultivated in Britain. It is to be
hoped that our government may, ere long, be induced to re-establish settle-
ments on the northern coasts of New Holland, whence the seeds of those
beautiful plants, to which we have particularly referred, may be again
obtained, and other methods of culture tried, in which their native habits
should
--

should be more consulted, than they were, some few years since, when one
or two collections only, about London, could, for a short period, boast of pos-
sessing living specimens. We will just observe, that these are considerations
of vegetable life well worthy of the attention of the intelligent botanic gar-
dener : it should ever be his business to imitate nature in the care and treat-
ment of her vegetable subjects, by affording them, as far as practicable, the
soil, the temperature, and situation in which they flourish in their native re-
gions, when these can be ascertained; and it should be no less the duty of
the botanic-traveller to communicate these and other circumstances, in re-
spect to the seasons of growth and cessation from it of plants of equinoctial
countries, in which he may have extended his labours, as all such will greatly
aid the skill of the intelligent cultivator.