CONTENTS XI 



Humulus (Hop). Humulus lupulus (Common Hop) — Root — 

 Stems — Leaves — Inflorescences — Flowers — Pollination, Fertili- 

 zation, and Development of the "Hops" — The Mature Fruit — • 

 Lupulin Glands — Geographical — Closely Related Species — 



Varieties — Composition^Uses of Hops 258-267 



Ficus (Fig) — Habit, Roots, Stems — ^Leaves — Inflorescence — 



Geographical Distribution, and Economic Importance 267-269 



Ficus carica (Common Fig) — Habit of Plant, and Stem — 

 Leaves — Inflorescence, and Flowers — Pollination — Crops of 

 Fruit in Caprifigs — Caprification — The Mature Fruit — Geo- 

 graphical — Types of Figs — Uses of Figs 269-276 



Cannabis sativa (Hemp) — Description — Geographical — Varie- 

 ties — The Hemp Industry in the United States — Preparation 

 of Hemp for Market — Uses of Hemp— Sisal Hemp — 

 References 2 76-283 



CHAPTER XXII.— PoLYGONACE^ (Buckwheat Family). 



Stems — Inflorescences — Flowers — Fruit — Key to Principal 



Genera 284-286 



Rheum rhaponticum (Rhubarb, Pie Plant) — Roots, Stems, 

 Leaves, Flowers — Fruit — Geographical, and Varieties — 



Uses 286-289 



Fagopyrum vulgare (Common Buckwheat) — Roots — Stems — 

 Leaves — Inflorescence — Flowers — Dimorphism and Pollina- 

 tion — Fruit — Seed — Geographical — Other Species — Varieties 

 — Key to Varieties of Common Buckwheat — Environmental 

 Relations — Uses — References 289-295 



CHAPTER XXIII.— Chenopodiace.*; (Goosefoot Family). 



Habit, Stems, Leaves — Inflorescence and Flowers — Fruit — 



Key to Principal Genera 296-298 



Spinacia oleracea (Spinach) — Description — Other Plants 

 Named "Spinach" — Groups of True Spinach — Key to Groups 



of Spinach 298-300 



Beta vulgaris (Beet) — Botanical Groups — The Wild Beet . . . 300-301 

 Sugar Beet — Habit — Root — Stems — Shape and Structure of 

 Beet (Tap Root and Hypocotyl) — ^Leaves — Inflorescence — 

 Flowers — Pollination and Fertilization — Fruit and Seed — 

 Seed Production — Germination, and the Seedling — Types of 

 Sugar Beets — Composition of Sugar Beets — Manufacture of 



Sugar — By-products of Manufacture 301-309 



Common Garden Beet — Types — Uses 310-312 



Chard 312-313 



Mangel-wurzels or Mangels — Types — Composition and 



Uses — References 313-31S 



