H. angusta'ta (narrow). April. Singapore.
heterophy'lla (various-leaved). April. Sa-
pectina'ta (comb-like). April. Isle of Luzon.
pedu'ta (doubly-lobed). May. East Indies.
HUMBLE PLANT. Mimo'sa pu'dica.
HU'MEA. (Named after Lady Hume.
Nat. ord., Composites [Asteracese].
Linn., 19-Syngenesia I-^qualis.)
Greenhouse biennial. Sow in heat, in spring ;
prick out and grow under glass ; place out of
doors in the heat of the summer ; house in good
time in the! autumn ; shift into larger pots as
wanted, and transfer to its blooming pots in
April, or plant out in good rich soil in May.
Single plants in a sheltered corner have a fine
H. e'legans (elegant). 6. Red. July. New
South Wales. 1800.
HU'MULUS. The Hop. (From humus,
the ground ; creeping on the ground if
not supported. Nat. ord., Hempworts
[Cannabinaceae]. Linn., 22-Di(ccia 5-
Hardy perennial twiner. Seeds and divisions
in spring ; deep loamy soil. It is useful for
summer shade, as it grows very quick.
H. lu'pulus (common. Hop). 15. Yellow.
variega'tus (striped- leaved}. 15.
Yellow. July. Britain.
HUMUS. When the putrefaction of
dead plants is completed, there re-
mains a soft black mass, known as
vegetable mould, or humus. One hun-
dred parts of the humus of wheat
straw have of extractive or apotheme,
rather more than twenty-six parts, and
the residue is lime, peroxide of iron,
phosphate of lime, and carbonaceous
matter. This apotheme is identical
with the humic acid of Liebig, the
ulmic acid of Braconnot, and the geic
acid of Berzelius. It contains car-
bon, 46.6 ; hydrogen, 20.0 ; oxygen ;
33.4=. It was once believed, indeed, is
still believed by a few men of science, j
that this apotheme is the immediate
fertilizing component of organic ma-
nures, being soluble under some cir-
cumstances, and entering at once into
the roots of plants, dissolved in the
moisture of the soil. But every re
lative research of more modern che-
mistry is against this conclusion, and it
is now tolerably certain, that a chief
nutritive portion of vegetable manures
is their carbon converted into car-
bonic acid, absorbed either in solu-
tion with the earth's moisture, or in
gaseous form by the roots.
HUNGARIAN LOTUS. Nymphte'a thcr-
HUNNEMA'NNIA. (Named after J.
ffunnemann, a botanical agent. Nat.
ord., Poppyworts [Papaveracese]. Linn.,
l-l-Polyandria, 1 -Monogynia.}
Greenhouse herbaceous perennial. Seeds in
spring ; rich soil ; will bloom the second year
in greenhouse treatment, or may be kept over
the winter in a dry, cold pit.
H./ianfz?/o7ta(Fumaria-leaved). 2. Yellow.
HUNTLE'YA. (Named after the Rev.
Mr. Hunlley^ a zealous collector of
plants. Nat. ord.. Orchids [Orchida-
cese]. Linn., '20-Gynandria l-Monan-
dria. Allied to Zygopetalum.)
Stove orchids. Slips of shoots, and dividing
the plant ; fibry peat, &c. ; grown in a high
moist temperature. Summer temp., 60 to 90 ;
H. melea'gris (Guinea-hen). 1. Yellow, brown.
July. South America. 1836.
sessiliflo'ra (stalkless - flowered). Violet.
June. Guiana. 1835.
viola'cea (violet-coloured). Violet. June.
HU'RA. Sand-box-tree. (The native
name. Nat. ord., Spnrgeworts [Euphor-
biaceo 1 ]. Linn., '2\-3foncecia 11-Mona-
delphia. Allied to Hippomane.)
Stove evergreen trees, with whitish yellow
flotrers. Seeds, and cuttings of ripe young
shoots, under a bell-glass, in sandy soil, and in
heat; rich loam and peat. Summer temp., 60
to 80 ; winter, 50 to 55.
H. crepi'tans (rattling ; equal - toothed}. 12,
South America. 1/33.
stre'pens (sounding ; unequal-toothed}, 12.
HURDLES of iron are the most eligible
modes of fencing, whether for perma-
nency or temporary purposes. They
are invisible at a short distance, elegant,
and durable. See Ha i liny.
HUSKY. The dung for a hotbed
when too dry is said to be husky.
C 497 ]
HUTCHI'NSIA. (Named after Miss
flutchins, an accomplished Irish cryp-
togamist. Nat. ord., Crucifers [Brassi-
caceee]. Linn., lu-Tetradynamia. Al-
lied to Lepidium. )
Annuals by seeds in April, in dry situations.
Herbaceous perennials by seed and divisions, in
spring, and cuttings, under a hand light, in
summer ; sandy loam, with a little peat or leaf
mould, and dry situations, such as banks or
H. petrat'a (rock). . White. April. England.
procu'mbens (lying-down). . White. May.
South Europe. 1823.
H. Alpi'na (Alpine). $. White. May. South
brevi'styla (short-styled). White. May.
calyci'na (/rge-calyxed). &. White. April.
cepecefo'lia (Cepeae-leaved). ^. Pink. June.
pu'milu (dwarf). June. Caucasus. 1821.
rotundifo'lia (round-leaved). $. White,
purple. June. South Europe. 1759.
stylo'sa (/o#-styled. i. White, pink.
June. Caucasus. 1825.
HYACI'NTHUS. The Hyacinth. (In
mythology, a beautiful boy, who, after
being killed, was transformed into this
flower. Nat. ord.., Lily worts [Liliacece] .
Linn., Q-Hexandria 1-Monogynia.)
Offsets from the bulbs, after the foliage has
died down in summer ; light rich sandy loam,
with a little leaf mould. A valuable bulb for
forcing. Best florists' kinds grown out of doors,
should be taken up after the foliage is withered,
kept in shelves and drawers until the end of
autumn, and then planted, and protected from
severe frost in winter, and frost and heavy
rains in spring, by an awning. For a brilliant
out-door display, where the kinds are not so
valuable, the roots may remain in the ground
many years if top-dressed, and the bulbs are
not too near each other. When grown in pots,
these should be deeper than usual in proportion
to the diameter nine inches are not too much. .
The compost we have found most suitable for
them in pots, is a good loam, three-fourths, |
and decayed cow-dung, two years old, one- '
fourth. In October they ought to be potted, j
and immediately plunged in tan or ashes, quite |
overhead, at least two inches. In potting, '
make the soil very firm under the bulb, to j
prevent the roots going directly down too soon. !
In a month after potting and plunging, a few j
may be brought into heat, and forced to flower !
about Christmas, and others may be brought ;
in, month after month, to supply flowers till
May. To grow them in water, glasses with a i
hollow cup at the top, to hold the bulb, are !
used. It is not good to begin too soon with !
glasses. December is quite early enough. After
being kept for a few days in slightly damped
sand, they should be placed in their glasses.
At flrst the water should only just touch the
base of the bulbs, and the glasses should be
kept in a dark closet until the roots have at-
tained the length of an inch. Two drops of
spirit of hartshorn may be added to the water
in each glass, when the bulbs are growing, and
whenever the water is changed. Dark-coloured
glass is always to be preferred, as the absence
of light is natural to all roots. By keeping the
glasses in a dark closet, until the roots are full
an inch long, the hyacinths will not get top-
heavy, but the roots being in advance of the
leaves, will preserve the plant balanced erect.
The bloom will also be finer, as the roots will
be in a state to nourish the leaves before these
are prematurely advanced. A piece of charcoal
put into each glass feeds the plant, and pre-
vents putridity in the water.
H. amethy'stinus (amethyst-colour). . Blue.
April. South Europe. 1759.
bruma'lis (winter). f. Various. February.
Orienta'lis (Oriental). |. Blue. March,
a'lbus (white), j. White. March.
fla'vus (yellow). 2- Yellow. March.
multiplex (double). 2. Variegated.
ru'ber (red). 2- Red. March. 1596.
semiple'nus (semi-double), g. Va-
riegated. March. 1596.
spica'tus (farg'e-spiked). $. Blush. Feb-
ruary. Zante. 1826.
vi'ridis (green). Green. August. Cape of
Good Hope. 1/74.
HYBANTHE'RA. (From hybos, a curve, -
and anthera, an anther, or pollen bag ;
referring to the curve in the gouty
anthers. Nat. ord., Asclepiads [Ascle-
piadacere]. Linn., b-Pcntandria '2~
Digynla. Allied to Pergularia.)
Stove herbaceous climber. Divisions of the
plant ; cuttings, when gowth commences ; sandy
loam and peat. Summer temp., 60 to 85 ;
winter, 50 to 55.
H. cordifo'lia (heart-shaped-teatwvZ) . Green,
yellow. May. Brazil. 1840.
HYBRIDIZING, or CROSS - BREEDING,
though not quite identical, have with
the gardener similar objects, viz., either
improving the beauty of his flowers, or
the flavour and prolificacy of his fruits
and culinary products. Hybridizing,
strictly speaking, is obtaining a pro-
geny between two different species, by
fertilizing the stigma of one with the
pollen of another; and cross-breeding
is obtaining a progeny between varie-
ties of the same species. The progeny
of hybrids cannot produce seed; but
cross-breds are fertile. Our Own obser-
vations, and those of others, justify the
[ 498 ]
following statements, as affording some
guide to the raiser of varieties:
1 . The seed-vessel is not altered in
appearance by impregnation from ano-
ther plant ; therefore, no hasty conclu-
sion of failure is justified by that want
2. The colour of the future seed, not
of that first hybridized, seems to be
most influenced by the male plant, if
its seeds and flowers are darker than
those of the female. Capt. Thurtell,
from his experimemts on the pelargo-
nium, found the colour and spot of the
petals to be more influenced by the
male than by the female parent. In-
deed, all experience proves that the
progeny usually, though not invariably,
most resembles in colour the male
3. Large stature and robustness are
transmitted to the offspring by either
parent, but Mr. Knight generally found
the most robust female parent pro-
duced the finest offspring.
4. Capt. Thurtell, from lengthened
observation and experiment, has ascer-
tained that the form of the petals fol-
lows most closely that of the female
5. Mr. Knight says that the largest
seed from the finest fruit that has
ripened earliest and most perfectly
should always be selected. In stone-
fruit, if two kernels are in one stone,
these give birth to inferior plants.
G. The most successful mode of ob-
taining good and very distinct varie-
ties, is to employ the pollen from a
male flower grown on another plant
than that bearing the female parent.
To avoid previous and undesired im-
pregnation, the anthers in the female
parent, if they are produced in the
same flower with the pistils, must be
removed by a sharp-pointed pair of
scissors, and the flower inclosed in a
gauze bag, to exclude insects, until the
desired pollen is ripe. Another effec-
tual mode of avoiding undesired im-
pregnation, is bringing the female
parent into flower a little earlier than
its congenors, and removing the an-
thers as above described; the stigma
will remain a long time vigorous if
7. When double flowers are desired,
if a double flower should chance to
have a fertile anther or two, these
should be employed for fertilization,
as their offspring are almost sure to be
HYDRA'NGEA. (From hydor, water,
and ayyeion, a vessel ; referring to the
cup form of the capsule or seed-vessel.
Nat. ord., Hydranyeads [Hydrangy-
aceee]. Linn., iQ-Decandria2-I)iyynia.)
Deciduous shrubs. Propagated by division
of the roots, cuttings of the ripened shoots, and
flourishing best in moist sheltered places. Hor-
tensis, the common garden Hydrangea, though
a little more tender, stands the winter well in
the southern parts of the island ; and though
cut down in most winters in the neighbourhood
of London, yet if a slight protection of mulch-
ing is thrown over the roots, the stems will rise
strongly, and bloom well after Midsummer, if
care be taken to remove all the weaker ones,
just as is done with a Fuchsia stool. This spe-
cies makes also fine ornaments in pots, and may
be propagated at almost any time ; the young
side shoots when two or three inches in length,
inserted in sandy soil and in heat, striking in a
few days, while the old stems will strike any-
where, but require their time. To grow it well
requires light, rich compost, well drained, and
abundance of water. The flower generally
appears first of a greenish colour, becoming of
a pale rose ; but in some districts the colour
becomes a beautiful blue. Notwithstanding all
the experiments that have been made, there is
still a little doubt as to the cause that produces
the change. When iron filings, and a solution
of alum are used, in some soils the blue colour
is produced, while the same means will not
produce it in others ; and other soils will almost
invariably produce this blue colour without any
peculiar matter whatever being added. The
loams at Kenwood, at Hampstead Heath, and
Stanmore Heath, and the peats at Wimbledon,
as well as some bogs near Edinburgh, are fa-
mous for producing this blue in the Hydrangea.
When trying artificially with iron filings and
alum water, we have had different colours on
the same plant. This variation is merely tem-
porary it cannot be propagated like a variety :
a cutting from a blue plant will produce a rose
one, unless the peculiar treatment be continued.
H. Belzo'nii (Belzoni's). 3. Blue. Japan.
Japo'nica (Japan). 3. Blue, white. July.
ceeru'lea (blue-lowered). 3. Blue,
white. June. Isle of Nepau. 1844.
stella' ta (starry -flowered). 3. Pink. July.
H. arbore'scens (tree-like). 6. White. July.
di 'scalar (two-coloured- leaved).
6. White, green, August. North
H. corda'ta (heart- leaved). White. July, Ca-
heteroma'lla (various - surfaced - leaved] . 4.
White. Nepaul. 1821.
horte'nsis (garden). 3. Pink. May. China.
ni'vea (snow - white - leaved) . 5. White.
August. Carolina. 1786.
glabe"lla (smoothish - leaved.) 5.
White, green. July.
quercifo'lia (Oak-leaved). 4. White. July.
HYDEA'STIS. Yellow Eoot. (From
hydor, water ; referring to the marshy
places where it grows. Nat. ord., Crow-
foots [Ranunculaceee]. Linn., 13-Poly-
aiidria 1-Monogynia. Allied to Adonis.)
Hardy herbaceous perennial. Division of the
root ; loam and peat ; moist situation.
H. Canade'nsis (Canadian). . Green. May.
North America. 1759-
HYDRO 'LEA. (From hydor, water,
and elaia, oil ; referring to the marshy
habitat, and oily feel of the leaves.
Nat. ord., Hydrophyls [Hydrophylacesej.
Linn., 5-Pentandria 2-J)igynia.)
Greenhouse herbaceous plants. Divisions,
cuttings, and seeds ; spinosa is a small aquatic,
growing best in peat and loam ; quadrivalvis
is also found in boggy places.
H. quudriva'lvis (four - divided) . Pale blue.
July. Carolina. 18U4.
spino'sa (thorny). 1, Blue. South Ame-
HYDROME'STUS. (From hydor, water,
and mestos, half; referring to the plant
living in water during the rainy season.
Nat. ord., Acanthads [Acanthacese],
Linn., I-Didynamia 2-Angiospermia.}
Stove evergreen shrubs. Cuttings of young
shoots, any time in spring and summer, in
sandy soil, and bottom heat ; peat and loam.
Summer temp., 60 to 80 ; winter, 48 to 55.
H. macula'tus (spotted). 2. Yellow. May.
HYDROPE'LTIS. (From hydor, water,
and pelle, a shield; referring to the
floating shield-like leaves. Nat. ord.,
Watershields [Cabombaceee], Linn.,
A very neat little hardy water plant, well
worth growing by the edges of an aquarium,
round a mass of water lilies, its nearest allies.
Division ; marshy soil ; should be protected in
H.purpu'rea (purple). Red. July. North
HYDROPHY'LLUM. Water-leaf. (From
hydor, water, and phyllon, a leaf. Nat.
ord., Hydrophyls [Hydrophyllace$e].
Linn.. 5-Penlandria l-Monogt/nia. Allied
Hardy herbaceous perennials from North
America, Divisions and suckers ; rich loam
and peat ; in marshy situations.
H, appendicula'tum (appendaged-ea^ed).
Blue. May. 1812.
Canade'nse (Canadian). . White. May.
Virgi'nicum (Virginian). . Blue. June.
HYDROWE'NIA. (From hydor, water
tainia, a band, referring to a triangular
band in the flower, secreting a liquid.
Nat. ord., Irids [Iridaceee]. Linn., 3-
Triandria I-Monogynia. Allied to Bea-
A pretty half-hardy bulb, with the aspect of a
tigridia, and flowers like a fritillaria. Seeds,
sown when ripe, or kept and given a little heat
in the spring ; division of the off-sets ; light
rich sandy loam ; taken up and kept after the
foliage is decayed, and planted out the follow-
ing spring. If left in the ground, and covered
to protect from rains and frosts, the plants will
be stronger than if the bulbs were kept dry all
H. loba'ta (lobed-flotvered). !, Yellow, pur-
ple. May. Lima. 1843.
melea'gris (spotted) .
HYGROMETER. An instrument for
ascertaining the quantity of moisture
in the air. Everything that swells by
moisture, and contracts by dryness, is
capable of being formed into one.
Every gardener, who has taken a cool
bunch of grapes into a hothouse well-
supplied with moisture, would, in the
grapes almost instantly being covered
with dew, see the principle upon which
the hygrometer acts. The colder the
grapes, the warmer the house, the more
the vapour contained in it, the sooner
would the dew be formed, and the more
plentiful its depositure. Pouring cold
water into a glass tumbler in similar
circumstances will be attended with a
similar result, dew will be deposited on
the outside of the glass; because, in
either case, the cold body condenses
the vapour in its neighbourhood, and
this is whatis called the dew point, being
that temperature at which moisture is
deposited from the surrounding atmo-
sphere upon any object of that particular
temperature. The drip in frames,
greenhouses, &c., is similarly caused.
The thermometer is the best instrument
I 500 ]
for shewing the temperature; and by ;
taking two similar ones, covering their j
bulbs with a fold of muslin or silk, j
keeping one dry and the other wet,
with a thread of lios-silk acting as a J
syphon from a vessel of water, the |
greater the difference of temperature
indicated by the moist and dry ther-
mometer; the greater the deficiency of
atmospheric moisture. The nearer the
temperature of the moist and dry bulb,
the nearer is the air to being saturated
with moisture. To obtain more perfect
details Daniel's Hygrometer is the best
instrument. It is represented in the
following figure. It consists of two
ether, and com-
the glass tube
which rests on
the support. The
ball which f onus
of the longer leg
is of black glass,
in order that
the formation of
dew on its sur-
face may be the
ble. It includes the bulb of a deli-
cate thermometer dipping in the ether,
its scale being inclosed in the tube
above the ball ; and whatever change
takes place in the temperature of
the ether is indicated by this ther-
mometer. The other ball is covered
with muslin. In making an obser-
vation it is first necessary to note
down the temperature of the air ; next
turn the instrument, so that when the
muslin-covered ball is heldiii the hand,
the ether may escape into the blackened
ball ; and it should also be held till the
included thermometer rises a few de-
grees above the temperature of the air,
when it should be replaced on the
support. Then drop, or gently pour, a
little ether on the muslin. The evapo-
ration of this extremely volatile sub-
stance produces cold; and attention
must be instantly directed to the black
glass ball and included thermometer.
The latter will be seen falling rapidly ;
and at length a ring of dew will appear
at the line which runs across the black
ball quickly, if the air is very moist,
slowly, if the air is dry. If the air is
very dry, no moisture will be thus de-
posited till the thermometer falls to
10, 20, or 30 below the temperature
of the air. But at whatever tempe-
rature the dew forms, that temperature
should be noted as the dew-point; and
the difference between it and the tem-
perature of the air, at the time, is the
degree of dryness according to the
indications of this hygrometer. Thus,
in a moderately dry day, let it be sup-
posed that the temperature of the air
is 05 in the shade, and that the muslin
requires to be kept moist, before dew
is formed, till the blackened ball con-
taining the ether has its temperature
reduced to 50, as indicated by the
included thermometer, there are then
said to be 15 of dryness. Again, sup-
posing the temperature is 85, and the
dew-point found, as before, to be 70,
the degree of dryness is still expressed
by 15 : but the quantity of moisture
diffused in the air is, notwithstanding,
somewhat greater in the latter case
than in the former. If 1000 represent
complete saturation, the quantity of
moisture, when the temperature is 65
and the dew-point 50, will be 009;
but when the temperature is 85 and
the dew-point 70, the moisture will be
represented by (i'23 ; these numbers
being ascertained by tables prepared
for the purpose. The difference, how-
ever, in such a case is so small it is not
worth taking into account in a horti-
cultural point of view. But as these
numbers can only be ascertained by
calculation, it is more convenient to
reckon by the degree of dryness, bear-
ing in mind that the dryness of the air
is indicated by the difference between
the temperature of the air and of tlui
dew-point. Thus, if the ring of dew is
formed as soon as ether is applied, and
only 1 difference is observable, the air
is nearly saturated ; if the difference is
5 to 10 the dryness is very moderate ;
while 15 to 20 of difference indicate
excessive dryness, and beyond tin's the
air is parching. Gard. Chron.
(From Itygros, moist)
[ 801 ]
and pldlco, to love ; referring to the
habitat of the plant. Nat. ord., Acan-
thack [Acanthacesej. Linn., l-Didy-
11 ami a 2-Angiospennia. Allied to Kuel-
Stove evergreens from the East Indies. Cut-
tings of young shoots, in sandy soil, in heat ;
peat and loam. Summer temp., 60 to 80 ;
winter, 45 to 55.
H. longifu'lia (long-leaved). Purple. June.
ri'ngens (gaping). . 1820.
salicifo'lia (Willow-leaved). Violet. June.
HYLESI'NUS PINI'PERDA. A species of
beetle which preys upon the pith of
young shoots of sickly or recently felled
Scotch and spruce firs. It is not very
injurious in this country.
HYLOTO'NIA EO'S.E. A saw-fly which
injures rose-trees seriously, by punc-
turing in rows their young shoots, and
depositing in the holes its eggs. The
best remedy is spreading a cloth be-
neath the trees in the evening, and
killing the insects shaken down upon it.
HYMEN;<K'A. Locust Tree. (From
Hymen, the god of marriage ; referring
to the leaflets being joined. Nat. ord.,
Leguminous Plants [Fabaceag]. Linn.,
W-Dccandria 1-Monogynia. Allied to
Fine, close-grained, hard wood, and the
resins Anime and Copal are produced by these
stove evergreen trees. Cuttings of firm young
shoots, in spring, inserted firmly in sand, co-
vered with a bell-glass, in bottom-heat ; peat
and rich loam. Summer temp., 60 to 85;
winter 55 to 60.
H. Candollia'na (Decandolle's). 30. White.
Cou'rbaril (Courbaril). 40. Yellow, purple.
West Indies. 1688.
verruco'sa (warty-podded). 20. White. Ma-
HYMEXANTHE'KA. (From hymen, a
membrane, and anthem, an anther, or
pollen bag. Nat. ord., Violetworts
[Violacese]. Linn., b-Pentandria 1
Monogynia. Allied to Alsodeia.)
Greenhouse evergreen shrub. Cuttings of
young shoots, getting a little firm, in spring,
in sand over peat, and well -drained, under a
bell-glass ; sandy peat, with a third of fibry
loam. Winter temp., 40 to 45.
H. dcnta'ta (toothed-teat-ed) . 6. Yellow. May.
New Holland. 1824.
HYMKXOCA'LLIS (From hymen, a
membrane, and AYI/OS, beautiful ; refer-
ring to the membraneous cup inside
the flower. Nat, ord., AmaryU-ins
[Amaryllidacefe]. Linn., K-He.rndria
I -Monogynia. Allied to Tancratium.)
They have all white flowers, and much re-
semble Pancratiums. Their seeds differ m
being large and green, the seeds of Pancratium
having a black, brittle skin. Offsets; rich