Key to the Families or Oki>ers. 



III. APETALOUS DIVISION. 

 Corolla (and sometimes calyx also) wanting. 



A. FIuM'ers uot lu cntkius. 



* Calyx and corolla both xoantiny. 



Saururace j;. — Flowers white, in a dense terminal 

 spike, nodding at the end. Carpels 6 or 4, 

 nearly separate 124: 



CERATorHYLLACE.!;, — Immersed aquatics, with 

 whorled finely dissected leaves. Flowers 

 monoecious 124 



• * Calyx superior (i.e., adherent to the ovary). 



Saxifragace^. — Small, smooth herbs, with incon- 

 spicuous greenisii-yellow flowers. Stamens 

 twice as many as the calyx-lobes, on a con- 

 spicuous disk . 46 



Halorage-E. — Aquatics. Leaves finely dissected 

 or linear. Stamens 1-8. Ovary 4-lobed or 

 (Hippuris) 1-celled 49 



Onagrace^. — Herbs, in ditches. Stamens 4. 



Ovary 4-celIed, 4-sided 49 



AristolochiacE-«. — Calyx 3-lobed, dull purple 



inside. Ovary 6-celled 116 



Santalace.e. — Low plants with greenish-white 

 flowers in terminal clusters. Calyx-tube pro- 

 longed, and forming a neck to the 1-celIed 

 nut-like fruit 124 



El-eagxacej:. — Shrubs with scurfy leaves. 

 Flowers dicecious. Calyx 4- parted, in the 

 fertile flowers apparently adherent to the 

 ovary, and becoming fleshy in fruit 123 



* * * Calyx inferior (plainly free from the ovary). 



+- Ovaries more than one and separate from each other. 



R.^xuxcuLACE^. — Calyx present, colored and 

 petal-like. Achenes containing several seeds, 

 or only one 2 



RuTACE.E. — Prickly shrubs, with compound trans- 

 parent-dotted leaves, and dicecious flowers ... 27 



-1 — 'v~Ovary cmly one, hut ivith more than one cell. 



Cras-sulace^e. — Herbs, in wet places. Pod 5- 



celled and 5-horned 48 



Phytolaccace.^. — Herbs. Ovary 10-celled and 



10-seeded 116 



I EuPHORBiACE.£. —Herbs. Ovary 3-celled, 3-lobed, 



protruded on a long pedicel. Juice milky . 125 

 Sapix KACE.E. — Trees. Ovary 2-celled and 2-lobed. 



Fruit two 1 -seeded samaras joined together. 



Flowers polygamous 31 



Rhamxace^.— Shrubs. Ovary 3-celled and 3- 



seeded ; forming a berry 29 



FiooiDEiE. — Prostrate herbs with whorled leaves. 



Ovary 3-celled, many -seeded 52 



URTirACE.t:. — Trees. Leaves simple. Ovary 2- 

 celled, but fruit a 1-seeded samara wingeil all 

 round. Stigmas 2 127 



H — 1 — \~Ovary only one, 1-ceUed and 1-seeded. 



Polygonace^. — Herbs. Stipules sheathing the 



stem at the nodes 119 



UrtU'ACE.e. — Herbs. Stigma 1. Flowers monw- 

 cious or dia-cious, in spikes or racemes. No 

 cliatf-like bracts among the tlouers. Or, 

 Stigmas 2 ; leaves palmately-compoiind 127 



Amarantace.*;. — Herbs. Flowers greenish or 

 reddish, in spikes, with chaff-like bracts inter- 

 spersed. Stigmas 2 118 



Chenopodiace.e. — Herbs. Flowers greenish, in 



spikes. No chaff-like bracts. Stigmas 2 116 



Oleace-E. — Trees. Leaves pinnately-comjioiind. 



Fruit a 1-seeded samara 115 



Urticace.e. — Trees. Leaves simple. Fruit a 



1-seeded samara winged all i-ound, or a drupe. 127 



Lacrace.e. — Trees or shrubs. Flowers dicecious. 

 Sepals 6, petal-like. Stamens 9, opening by 

 uplifting valves 122 



Thymele.vc'e.e. — Shrubs with leather-like bark, 

 and jointed branchlets. Flowers perfect, pre- 

 ceding the leaves. Style thread-like 123 



B. Flowers in catkins. 



* Sterile or staminate flowers only in catkins. 



Juglandace.e. — Trees with pinnate leaves. Fruit 



a nut with a husk 130 



Cupulifer.*:. — Trees with simple leaves. Fruit 

 one or more nuts surrounded by an involucre 

 which forms a scaly cup or bur 131 



» * Both sterile and fertile flowers in catkins, or catkin- 

 like heads. 



Salicace.E. — Shrubs or low trees. Ovary l-celled, 

 many-seeded ; seeds tufted with down at one 

 end 136 



PlataNACE.E. — Large trees. Stipules sheathing the 



branchlets. The flowers in heads 130 



Myricace.*;. — Shrubs with resinous-dotted, usually 

 fragrant, leaves. Fertile flowers one under 

 each scale. Nutlets usually coated with waxy 

 grains 134 



Beti'LACE.e. — Trees or shrubs. Fertile flowers 2 

 or 3 under each scale of the catkin. Stigmas 

 2, long and slender 1 35 



SUB-CLASS II. GYMNOSPERMS. 



Ovules and seeds naked, on the inner face of an open 

 scale ; or, in Taxus, without any scale, but surrounded 

 by a ring-like disk which becomes red and berry-like 

 in fruit. 



CoxiFER.E. — Trees or shrubs, with resinous juice, 

 and mostly awl-shaped or needle-shaped leaves. 

 Fruit a cone, or occasionally berry-like 139 



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