136 KEY TO SUB-CLASSES, ORDERS AND GENERA. 
XVIII—DIPTEROCARPACE A—cont. 
broad, generally equidistant, the horizontal cells of these in many cases very long 
38 mm. in Dipterocarpus alatuws. The longitudinal cells, as well as the resin ducts 
in the younger wood, are filled with essential oil. Many species have a distinct dark- 
coloured heartwood. Resin ducts, vessels, fissures and other cavities in the old wood 
are filled with resin. Biological features--As a rule large trees, with tall regularly 
shaped trunks. With few exceptions they do not bear flowers and seed until they 
have attained a considerable age. As a rule they seed annually, though the quantity 
of seed produced varies from year to year. ‘Ihe seed germinates soon after ripening, 
in some cases before it falls to the ground. Several species are gregarious and form 
forests of considerable extent, in whi ch they prev ail over their companions. .| [ Botanical 
note.-—Ancistrocladus, shown by Hooker in this order, is now classed in a distinct 
order. Balanocarpus is not entered in Hooker; but, under Hopea, is entered Hopea 
longifolia, which is really Balanocarpus utilis. | 
(1) Calyx tube free, enclosing fruit, 2 lobes expanding into long wings; 
stipules large, amplexicaul ; stamens many ; style filiform :— 
lxxx—Dipterocarpus. 
(II) Calyx valvate in bud, with equal spreading segments accrescent, but 
not expanding into wings, in fruit; stipules small, fugacious; stamens 15, 
anthers short, oval, appendix of connective short obtuse ; no stylopodium (fleshy 
prolongation of the ovary) :— nec Ixxxi— Vatica, 
(LIL) Calyx imbricate in bud, 2-3 outer segments accrescent, and 
forming in fruit long wings ; connective usually awned :— 
(i) Wings of calyx 2; stamens 15 (rearely 10), appendix of connective 
long, pointed ; stylopodium as a rule large:—: ... Ses .. Ixxxiii—Hopea. 
(ii) Wings of calyx 8; stamens 15 or many, appendix as a rule long 
pointed :— ee .. Ixxxii—-Shorea. 
(IV) Calyx imbricate i in ‘bud, accrescent but not into lone wings : — 
(i) Lobes of fruiting calyx equal, reflexed, and shorter “than fruit ; stamens 
many, anthers linear- -oblong with 1—2 appendages : _ ee Ixxxiv—Vateria. 
(ii) Lobes of fruiting calyx slightly and evenly enlarged, thick, sometimes 
woody ; stamens 10—15, appendage of connective ie pointed; stylopodium 
generally distinct :— ees “6 sod 46 ‘ ... Ixxxy—Balanocarpus. 
XIX—MALVACEA— 
[Botanical note.—Brandis places Kydia in section (IIL) beiow with Cullenia, Hooker 
and Prain place it in section (1) as shown here. | 
(I) Staminal tube truncate, or only slightly divided at the apex ; sepals leafy ; 
leaves simple, entire or lobed :— 
(i) Ripe carpels separating from the axis as dehiscent or indehiscent 
coccl :— 
(1) Styles as many as carpels :— 
(A) Bracteoles 3—6 ; flowers racemose, pale purple red :— ...lxxxvi—Lavyatera. 
(B) Bracteoles O ; carpels 1-seeded ; ovules solitary pendulous ; fore- 
noon-to-noon flowering plants w ‘ith small leaves and flowers :— 
Ixxxvili—Sida. 
(C) Bracteoles 0; carpels l-or more-seeded ; ovules 2 or more; after- 
noon orevening ficwering plants with rather large leaves and 
medium flowers : — Ixxxix—A butilon. 
(2) Styles twice as many as carpels, which are 1-seeded :— 
(A) Carpels opposite the sepals, dehiscent after separating ; bracteoles 
A «+. xei—Pavonia. 
(B) Carpels opposite the petals, indehiscent after separating ; bracte- 
oles 5, connate :— ws Aa ae .. xc—Urena. 
Gi) Ripe carpels forming a normal capsule : — 
(1) Stigmas spreading ; seeds reniform :— 
(A) Ovary 10-celled, 1 ovule in each cell :— Ms «. xcii—Decaschistaa, 
(B) Ovary 5- (or spuriously i celled, 3-or more ovules in each cell ; 
flowers axillary :— xciii—Hibiscue. 
(C) Ovary 3-celled, 2 ovules in 1 each cell ; flowers panioled : — 
xcvi—Kydia. 
(2) Style club-shaped with radiating stigma; ovary 5-celled :— 
Ixxxvii— Lagunaria. 
