SIMARUBACEiE. , 377 



aroma, balsam, or resin, aud the fruit always indehiscent. Two anomalous 

 Arizono-Mexican genera are appended. 



Tribe I. SURIANE^E. Carpels entirely distinct, neither ovaries nor styles united. 

 Flowers perfect. (Cneoridium would belong here except for the glandular-punctate 

 foliage and rutaceous odor.) 



1. SURIANA. Calyx 5-parted, persistent. Petals 5, imbricated in the bud, unguiculate. 

 Stamens 10, with slender filaments, those opposite the petals shorter or sometimes wanting. 

 Disk obscure or aduate to base of calyx. Carpels 5, opposite the petals ; ovaries globular, 

 hairy, with 2 collateral ascending campylotropous ovules ; styles filiform ; stigma capitellate. 

 Fruit akeniform ; embryo horseshoe-shaped ; cotyledons thick, oblong, incumbent. 



Tribe II. SIMARUBE-iE. Carpels (1-ovuled) united only at base or by their 

 styles, in fruit becoming distinct and forming 



* Samaras : exotic. 



2. AILANTHUS. Flowers polygamo-dicecious ; the ? with smaller mostly sterile sta. 

 mens ; d with only a rudiment of pistil. Calyx small, 5-parted. Petals 5, oblong, valvate- 

 induplicate in bud, or the tips imbricated. Stamens borne on the base of a 10-crenate disk, 

 in sterile flowers 10, with oval or oblong anthers, in fertile flowers sometimes fewer and 

 with small or abortive anthers. Carpels 2 to 5, distinct (but the medial styles connate ; the 

 thickened stigmas divergent), in fruit becoming linear-oblong samaras bearing the rounded 

 seed at the middle of the thin and veiny ventrally emarginate wing ; albumen little ; cotyle- 

 dons orbicular. 



* * Drupes. 



3. SIMARUBA. Flowers dioecious. Calyx short, 5-toothed. Petals 5, imbricated in the 

 bud, connivent below, widely spreading above. Stamens 10, borne on a hemispherical disk 

 or torus (in fertile plant only rudimentary) ; filaments with scale-like appendage at base 

 inside. Carpels 5, slightly cohering, with styles united into one and a 5-lobed stigma. 

 Drupes 1 to 5, not stipitate ; embryo with thick aud fleshy cotyledons and retracted radicle. 

 Leaves pinnate. 



4. CASTELA. Flowers polygamo-dicecious, 4-merous. Calyx 4-parted, small. Petals 4, 

 oblong, imbricated in the bud. Stamens 8, inserted under an 8-creuate disk ; tiiose of fertile 

 flowers smaller and commonly imperfect ; filaments short, not appendiculate. Carpels of fer- 

 tile flowers 4 , styles short, united below, revolute and introrsely stigmatose above. Drupes 

 small, subsessile, with thin flesh and crustaceous endocarp ; seed globose-ovate, with little al- 

 bumen ; cotyledons orbicular, plano-convex, not enclosing the short radicle. Leaves simple. 



5. HOLACANTHA. Flowers dioecious. Calyx 5-8-parted. Petals 7 or 8, obovate-spatu- 

 late, imbricated in the bud. Stamens 12 to 16 in sterile flowers, their subulate filaments 

 hairy-tufted at base, 6 to 8, and with small imperfect anthers in the fertile. Disk annular, 

 crenulate. Carpels 6 to 10, lightly cohering around a low conical axis; styles divergent, 

 terminal, subulate, above introrsely stigmatose. Drupes small and dry, stellately divergent, 

 sessile, ovoid, tardily separating from the conical fissile axis ; embryo amygdaloid, in thin 

 albumen ; radicle nearly retracted within the base of the obovate flat cotyledons. Leaves 

 reduced to mere scales on grown plants. 



Tribe III. PICRAMNIE^Si. Carpels consolidated into a 2-5-celled ovary; their 

 styles more or less united. 



* Genuine. 



6. PICRAMNIA. Flowers dioecious. Calyx 3-5-cleft. Petals 3 to 5, narrow. Stamens 

 as many as petals and opposite them ; filaments slender, naked ; in fertile flowers reduced 

 to vestiges. Ovary 2-3-celled, with a pair of ovules in each cell. Fruit an olive-shaped 1- 

 seeded berry ; no albumen ; embryo nearly entire. Leaves imparipinnate. 



* * Anomalous, of uncertain affinity, green-thorny shrubs with habit of Ilolacantha : 

 flowers hermaphrodite : no obvious hypogynous disk : anthers ovate. 



7. KCEBERLINIA. Sepals 4, small, deciduous. Petals 4, convolute-imbricate in the bud, 

 deciduous. Stamens 8 ; filaments thickened in the middle, subulate-attenuate. Ovary ovoid. 



