AN ENCYCLOPADIA OF HORTICULTURE. 
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501 
Ophrys - continued. 
broadly margined with maroon-purple. Z. linear-oblong. Stem 
4in. to 12in. high, bearing several flowers. South Europe, 1818. 
(B. M. 5844; B. R. 370.) 
O. tenthredinifera (sawfly- bearing). fl. varying in colour; 
petals spreading ; lip villous, oblong, obovate, the apex bilobed, 
appendiculate. April and May. Stems leafy. k. Yin. South 
Europe, 1815. (B. M. 1930; B. R. 205, 1093.) “igi 
O. vespifera (wasp-bearing). A synonym of 0. lutea. 
OPLISMENUS (from hoplismenos, awned; referring 
to the awns). Syns. Hekaterosachne, Orthopogon. ORD, 
Graminee. A small genus (three or four species) of 
stove or greenhouse grasses, allied to Panicum, broadly 
dispersed over the tropical and sub-tropical regions of 
the globe. Spikelets one-flowered, articulated with the 
pedicel; glumes four; panicles unilateral. Leaves nar- 
rowly or broadly lanceolate, flat. These somewhat large- 
leaved grasses are of easy culture; they grow freely 
in a mixture of loam, leaf mould, and sand, and make 
nice plants for table decoration, &c. They are propagated 
by division; or by seeds, which are freely produced. 
The two species mentioned below succeed either in the 
stove or greenhouse, : ; 
O. hirtellus (slightly-hairy).* Jl., sheath pilose ; spikes distant; 
common axis pubescent ; spikelets three to ten, pubescent ; lowest 
awn smooth, bluntish, three to five times as long as its glume ; 
third glume shortly awned, furnished with a palea. June and 
July. (. lanceolate, acuminate, undulate, puberulous, 1łin. to 
2hin. long. West Indies, 1795. SYN. Orthopogon hirtellus. 
O. loliaceus (Tares). A., sheath glabrous, ciliate or pilose ; spikes, 
usually oblong ; common axis nearly glabrous ; spikelets fascicled ; 
lowest awn three or four times as long as its glume; third glume 
shortly awned, furnished with a palea. July and August. l. ob- 
py -lanceolate or lanceolate, acuminate, 2in. to 4in. long. Trini- 
1820. SYN- Orthopogon loliaceus. 
OPLOTHECA (of Nuttall). Included under Fræ- 
lichia. i 
OPOPONAX CHIRONIUM. A synonym of Mala- 
baila Opoponax (which see). 
OPORANTHUS. Included under 
(which see). 
OPPOSITE. Placed on opposite sides of some “other 
body or thing, and on the same plane. 
OPUNTIA (the old Latin name used by Pliny, and 
said to be derived from the city of Opus). Indian Fig; 
Prickly Pear. ORD. Cactee. A genus of greenhouse, or 
hardy succulent trees or shrubs, natives of the tropical and 
warm regions of America; some of the species have become 
widely naturalised in the Old World. About 150 species 
have been described, but many of these are not sufficiently 
distinct to merit specific rank. Flowers yellow, red, or 
purple, lateral; calyx tube not produced above the ovary; 
lobes numerous ; petals numerous, connate at base, spread- 
ing; stamens many-seriate. Berry pear-shaped, tubercled. 
Leaves scale-like, deciduous. Stem terete at base, 
branched ; branches articulated, fiat, compressed, globose 
or sub-cylindrical, tubercled; tubercles tomentose, spiny, 
the young ones leafy. 
The cultivation of Opuntias is very easy. All that is 
necessary for plants in pots is to secure thorongh drain- 
age, and give all the light possible. Formerly, broken 
brick rubbish was supposed to be essential to their 
well-being, but good loam alone will do quite well. 
Powdered bricks, mixed with the loam, however, suit 
the smaller-growing kinds, and insure rapid drainage. 
During winter, a smaller supply of water is required; 
indeed, when at rest, the plants should be kept almost 
dry. The hardy species are extremely interesting, and 
grow freely in sunny spots in the open air, provided 
some means be adopted to guard against superabundance 
of moisture. Some of them, in their native habitats, 
withstand much more cold than ever is experienced in 
Britain; but the dry air, or the covering of snow, pro- 
tects them. An ordinary hand-light, placed over the 
* plants, is shelter enough, provided the position in which 
Sternbergia 
Opuntia—continued. 
‘they are placed is dry and efficiently drained. Opuntias 
may be propagated by means of the branches, or portions 
of them; these should, after being cut off, be laid on a 
dry shelf for a time, and then planted or laid on well- 
‘drained pots of loam and brick-dust; but very little 
water should be given until roots are gmitted. Seeds, 
too, are readily raised; the appearance of the seedlings 
Fic. 749. SEEDLING OPUNTIA, showing Mode of Germination. 
is shown in Fig. 749. The following extracts from the 
“ Transactions of the Horticultural Society” are interest- 
ing as showing what may be done in a Surrey garden; 
they are from a paper On the Treatment of the Cactus 
Opuntia, or Prickly Pear; under which it will perfectly 
mature its fruit in the open air of England,” read on 
Zrd Sept., 1816, communicated by Mr. John Braddick, 
Thames Ditton: “ Having heretofore observed that the 
plant, in its wild state, delighted in a dry soil amongst 
rocks near the skirts of the sunny sides of the forests 
{the writer is speaking of Virginia], I, in consequence, 
planted it in the compost described below, placed in a 
sheltered position open to the sun. The first plant that 
I turned out has lived in the open ground of this country _ 
for six or seven years, during which period it has 
endured one exceeding hard winter, and several trying 
springs; and in all, except the first two years, it has 
never failed to ripen its fruit and seeds, so that it may 
be now considered decidedly naturalised. It is now 
growing vigorously; and, although the present season 
has been decidedly unfavourable, yet I doubt not but it 
will produce a plentiful crop of flowers, and ripen its 
fruit fit for the table during the course of the next 
month. . . The compost used by me for growing 
the Cactus Opuntia is the following: One half is car- 
bonate of lime, for which lime rubbish from old build- 
ings will answer; the remaining half consists of equal 
portions of London clay and peat earth, having the 
acid neutralised by barilla; these are intimately blended 
and sifted. One square yard of this compost I conceive 
to be sufficient for one plant, which must be placed in 
the mi of a small artificial hillock, raised eighteen 
inches above the surface of the ground, which ground 
should be rendered perfectly dry, if not naturally so, 
by under-draining. Neither the leaves, flowers, nor 
fruit should ever be suffered to touch the ground; but 
they should, as constantly as they are produced, be kept 
from the earth, by placing stones, pebbles, flints, or 
