130 KEY TO SUB-CLASSES, ORDERS AND GENERA. 
GYMNOSPERM Ai. 
(1) Leaves or scales undivided, opposite, alternate, or in clusters on the 
branches :— 
(i) Perianth present in flowers of both sexes, of male membranous lobed, of 
female utricular; leaves large opposite on swollen-jointed branches; seed 
drupaceous :-— ots 0 : abe 00 Ae CXI—GNETACER. 
(ii) Perianth absent from flowers of both sexes ; leaves usually alternate 
or foscicled, ana linear or subulate and rigid, sometimes scale-like, rarely 
(Ginkgo, Podocarpus, Agathis, Araucaria) broad; fruit usually a cone, rarely 
(Ginkgo, Taxus, Podocarpus) subdrupaceous :— ive ie ... OXITI—ConmiFrERa&. 
(II) Leaves very large, pinnatisect or bipinnate, clustered (palm-like) at 
the apex of the stem; perianth absent from the flowers of both sexes ; male 
flowers in terminal cones formed of numerous fleshy peltate scales with crowded 
anthers below, females of flat carpellary leaves (carpophylls) crowded round the 
apex of the stem, or cones of peltate scales ; seed large drupaceous :— 
CX1II—CycaDAace&. 
MONOCOTYLEDONKS. 
(I) Perianth 2-seriate, segments of both series corolline, or if only the inner 
series corolline then its segments much larger than those of the outer calycine 
series :— : 
(i) Seeds very small, often minute, without albumen; Ovary inferior 1- 
locular with 3 parietal placentas :—— 
(1) Outer segments corolline like the inner :— 
(A) Flowers irregular, usually markedly so, from the modification of a 
segment of the inner series as a lip (labellum) ; stamens and 
pistils confluent as a column bearing a single sessile or subsessile 
anther : epiphytes or climbers :— oe «. CXIV—ORCHIDACER, 
(ii) Seeds conspicuous with copious albumen :— 
(1) Ovary inferior :-- 
(A) Flowers very irregular, outer series of perianth calycine ; perfect 
stamens either 1 with 5 reduced to staminodes, or 5 with one 
staminode ; seeds often with an aril :— 
CX V—SclIraMINAcEm. 
(B) Flowers regular or only slightly irregular, both series of perianth 
segments corolline; stamens 6, very rarely (AMARYLLIDACER, 
sometimes) more numerous, or if 3 only then (AMARYLLIDACEA, 
sometimes) opposite the inner perianth segments, or if only the 
stamens opposite the outer perianth segments perfect (Drosco- 
REACE®M, some times) then the locules of the ovary only 
2-ovuled :— 
(2) Ovary 3-locular, or if 1-locular (AMARYLLIDACE, rarely), then the 
stamens not hooded :— 
(x) Flowers i-sexual very small; stamens 6, or if 3 these opposite 
the outer perianth segments ; Stems scandent :— 
CXVI—DioscoRFAcEm. 
(8) Flowers hermaphrodite, conspicuous or very large ; Stamens 6, 
rarely more, or if 3 these opposite the inner perianth segments ; 
ovary loculi many-(rarely 1—2) ovuled, embryo very small 
embedded in albumen ; stems not scandent :— : 
CX VI—AMARYLLIDACER 
(3) Ovary superior with embryo completely enclosed within the 
albumen, or if ovary } inferior (ROXBURGHIACE®, sometimes) then the perianth 
9-merous and the ovary l-locular ; flowers regular or only slightly irregular ; both 
riesof perianth present, corolline, isomerous :— 
(A) Perianth segments 2-merous ; stamens 4; ovary 1-locular :— 
CX VIII—RoxBurGHIAcEm, 
(B) Perianth segments 3-merous; stamens 6 or 8; inflorescence 
various, axillary or terminal, but never a 1-leafed scape :— 
CXIX—Liniacen, 
(II) Perianth if 2-reriate with the segments of both series calycine, or if those . 
of the inner corolline then not larger than those of the outer series, or perianth 
