120 KEY TO SUB-CLASSES, ORDERS AND GENERA. 
THALAMIFLORA—cont. 
(6) Piacentas 2—5 parietal, or intruded to the axis; stamens as 
many as petals; petals regular ; leaves alternate or subverti- 
cillate :— XI—PITTOsPORACEX, 
(vy) Placentas free central ; stamens usually twice as many as 
petals ; petals reguler, slightly connate below, or O ; leaves 
scale-like, minute, alternate :— ... es XITI—TAMARtscacem, 
(6) Placenta basal with 1 erect, or laterally fixed, ovule ; styles 3 ; 
stamens usually twice as many as petals; petals ‘contorted, 
slightly connate below ; leaves terminally ‘tufted, alternate ; 
branches hooked, cirrhose : i— .. X&XIJ—ANciIstTROoc LADACER. 
(b) Ovary 2-or more-celled; or, if 1-celled (PoLYGALAcEA, 
Xanthophyllum), then the flower not isomerous ; seed 1 (iess 
often 2) to each cell of fruit, and either erect or pendulous; if 
more than 2 and attached to inner angle of cells (GERANIACEA, 
Averrhoa, Impatiens), then either with regular flowers and 
alternate pinnate leaves, or with opposite or alternate simple 
leaves and irregular flowers :— 
(a) Seeds pendulous :— 
(*) Flowers usually anisomerous (sepals 5, stamens 8) ; filaments 
cormate in a sheath usually adnate to petals; sepals and 
petals generally irregular; ovary 1—2-locular; leaves 
simple alternate ; Deer iia) sat XII—PoLyGaLaces, 
(**) Flowers isomerous ; disk usually present :— 
(+) Leaves compound opposite ; stamens quite free, 10, or 
(Peganum) 12—15 :-- 20 ... XXIV—ZyYGorHYLLACE”. 
(+t) Leaves simple, or, if compound, alternate ; stamens more 
or less united :— 
(§) Ovules in each carpel 2, collateral; cells of fruit, if 
capsular, 2 chambered, each chamber 1-zeeded ; leaves 
always alternate simple; stamens always 5; petals and 
sepals always regular :— ... 500 ... AMXITI—LInNAcEs, 
(§§) Ovules in each carpel more than 2; stamens either 10 
with regular perianth and compound alternate leaves, 
or 5 with irregular perianth, connate anthers, and 
simple alternate or opposite leaves :— XXV--GERANIACE%, 
(8) Seeds erect; flowers isomerous or anisomerous : ieaves usually 
alternate paripinnate, rarely simple or digitately compound, 
more rarely opposite and odd pinnate ; seed often arillate :-— 
XXXVITI—SapinpaceEx, 
[Note.—Sir D. Brandis separates this into three distinct orders, as below : } 
(*) Leaves opposite, stipulate, 3-foliate or imparipinnate, leaflets 
stipellate ; flowers regular, 2-sexual 5-merous ; stamens 5, 
inserted outside the disk ; ovary 3-celled, ovules 2—-or more 
in each cell, embryo straight in fleshy albumen :— 
XXXVIII-A—STAPHYLEACE, 
(**) Leaves opposite, exstipulate ; flowers regular polygamous ; = 
disk generally annular ; stamens inserted or upon (rarely in 
side) the disk ; filaments free, as a rule glabrous ; ovary of 
2 carpels 2-celled, 2-lobed ; fruiting carpels winged 
albumen O :— af XXXVIII-B—AcErRscex, 
(***) Leaves alternate, simple or pinnate (except Asculus, oppo- 
site digitate) ; flowers regular or zygomorphic, generally 
polygamous ; sepals (or calyx) small, cupshaped, campa- 
nulate or tubular in A/sculus) ; petals usually 4, generally 
with scales or tufts of hair: stamens inserted between 
disk and ovary ; filaments generally hairy ; disk frequently 
unilateral (inconspicuous in Dodonewa); ovary usually of 
3 carpels, 3-celled, often 3-lobed, albumen O, embryo as 
arule curved :— ... aa we XXXVITI-C—Sapinpacem. 
(ii) Sepals more or less united at the base :-— 
(1) Stamens indefinite, (rarely 10}; calyx-lobes 5, often enlazged in 
fruit ; petals 5, contorted; leaves alternate, stipulate, simple, not gland- dotted ; 
trees with resinous sap :— ... aa 335 + ft XVIII—DiprerocarPAaces. 
