156 REAUMURIACE. 
Cult. Elegant little shrubs of easy culture; they thrive best 
in a mixture of sandy loam and peat; and young cuttings readily 
strike root under a hand-glass. 
II]. HOLOLA’CHNA. This genus having already been de- 
scribed under the order Tamaracinee, it is only necessary here 
to refer to vol. II. p. 728. where all the details of the genus will 
be found. 
Orver CXVII. CA’CTEZ (this order contains the genus 
Cactus, and all the genera recently separated from it). D.C. 
prod. 3. p. 457. mem. cact. in mem. mus. vol. 17. p- 1-119. 
—Cactoidew, Vent. tabl. 3. p. 289.—Nopalee, D. C. theor. 
elem. 216.—Cacti, Juss. gen. p. 310. exclusive of Grossu- 
lariéze.—Opuntiacee, Juss. dict. 35. p. 144. exclusive of Gros- 
sulariée. H.B. et Kunth, nov. gen. amer. 6. p. 65.—CaActus, 
Lin. gen. no. 613. Willd. enum. hort. berol. p. 30. Link. 
enum. 2. p. 21. &c. 
Calyx composed of many sepals, usually indefinite in number, 
and confounded with the petals, united and adnate a great 
length to the ovarium; with the tube smooth in the genera Mam- 
millaria, Melocdctus, and Rhipsalis ; or with the lobes of the se- 
pals crowning the fruit, and having the tube scaly as in the genera 
Céreus, Opintia, and Peréskia. Petals disposed in two or more 
series, hardly distinguishable from the inner sepals, and some- 
what united to them ; sometimes irregular, and disposed in a long 
tube at the base, but distinct at the apex, as in the genera Mam- 
millaria, Melocdctus, and Céreus ; sometimes equal and distinct 
to the very base, forming a rotate corolla, as in the genera Opún- 
tia, Peréskia, and Rhipsalis. Stamens indefinite, disposed in 
many series, more or less cohering with the petals or inner 
sepals; filaments slender, filiform: in the genus Opintia they 
are irritable to the touch; anthers ovate, versatile, 2-celled. 
Ovarium obovate, fleshy, 1-celled: with numerous ovula, ar- 
ranged upon parietal placentas, which are equal in number to the 
lobes of the stigma. Style filiform, sometimes full and sometimes 
fistular ; stigmas numerous, either spreading or collected into a 
cluster. Fruit fleshy, 1-celled, many-seeded, either smooth and 
crowned by the calyx, or covered with scales, scars, or tuber- 
cles, and umbilicate at the apex. Seeds, when young parietal, 
but when mature imbedded in the pulp with which the cells are 
filled, oval or obovate, without albumen. Embryo either straight, 
curved, or spiral ; with a short, thick, obtuse radicle ; cotyledons 
flat, thick, foliaceous in Opúntia and other leaf-bearing genera, 
very small in Melocáctus, and perhaps almost obsolete in Mam- 
millaria and other leafless genera. 
This order contains fleshy or succulent shrubs, very variable 
in habit. Stems usually angular, winged, or regularly beset with 
tubercles, rarely terete, usually jointed; joints compressed. 
Leaves usually wanting, but when present small, caducous, and 
terete, sometimes like those of Sedum, rarely flat and expanded, 
sometimes alternate and disposed in a spiral order, always gla- 
brous and fleshy. Prickles or bristles disposed in fascicles, 
rising from the axils of the leaves; in the leafless genera the 
fascicles of spines are disposed on the angles of the stem, rising 
II, Hotroracnuna. CACTEZ. 
from tubercles. Flowers very variable, showy, or minute, usually 
solitary, sessile, rarely in fascicles, ephemeral, expanding by 
night or by day. 
It has already been remarked, on more than one occasion in 
this work, that the state of that remarkable distention or in- 
crease of cellular tissue of vegetables, from which the name of 
succulent is derived, is no indication of natural affinity, but rather 
to be considered a modification of structure, which may be com- 
mon to all tribes. Hence the immediate relationship of Céctee 
is neither with Euphorbiacee, nor Laurinee, nor any other tribe 
of succulent plants, but with Grossulariée, in which no tendency 
whatever to an increase of cellular tissue exists. Through Rhip- 
salis, which is said to have a central placenta, Cdctee are con- 
nected with Purtulacee, to which also the curved embryo of the 
section of Opuntidcee probably indicates an approach. De Can- 
dolle further traces an affinity between these plants and Ficoidee. 
For an elaborate account of this order, see his Memoir above 
quoted. 
The fruit is very similar in properties to those of Grossularia, 
some being refreshing and agreeable to the taste, others mucila- 
ginous and insipid; they are all, however, destitute of the ex- 
cessive acidity of some gooseberries and currants. The fruit of 
Cactus Opúntia, has the property of staining red the urine of 
those who eat it. The juice of Mammillaria vulgaris is remark- 
able for being slightly milky, and at the same time sweet and 
insipid. 
Synopsis of the genera. 
Trise I. 
Orvuxtia`ceæ. Ovula, and therefore the seeds, fixed to the 
parietes of the fruit. 
1 Mammitra‘ria. Tube of calyx adhering to the ovarium; 
lobes 5-6, coloured, crowning the young fruit. Petals 5-6, 
hardly distinguishable from the calyx. Stamens disposed in many 
series. Stigma 5-7-cleft. Berry smooth. 
2 Metoca’crus. Tube of calyx adhering to the ovarium; 
lobes 5-6, petaloid, crowning the young fruit. Petals 5-6, united 
into a long tube with the sepals. Stamens disposed in many 
series. Stigma 5-rayed. Fruit smooth. 
3 Ecutnoca’crus. Sepals numerous, imbricate, adhering tO 
the ovarium : outer ones in the form of an involucrum: inner 
ones petal-formed. Stamens numerous. Style multifid at the 
apex. Berry scaly from the remains of the sepals. 
4 Cr‘reus. Sepals very numerous, imbricate, adnate to the 
base of the ovarium, united into an elongated tube: outer ones 
shorter and like a calyx: middle ones longer and coloured, 
innermost ones petal-formed. Style multifid at the apex. Berry 
areolate, tubercular or scaly from the remains of the sepals. ; 
5 Epipny'trum. Tube of calyx very long, furnished with 
remote scales; limb of corolla multifid, rosaceous or ringent 
Branches flat. 
6 OPV'NTIA. Sepals numerous, leaf-formed, adnate t 
ovarium: upper ones flat and short: inner ones petal-formed, 
obovate and expanded, with no tube above the ovarium. Sta- 
mens numerous, shorter than the petals. Stigmas numerous 
o the 
as secretin, a iii a. i a 
Dam — 
