KEY TO THE FAMILIES OF FLOWEEIj^G PLANTS 

 DESCRIBED IN THIS FLORA 



CLASS I 



GYMNOSPERMS. Ovules not enclosed in an ovary. 



Trees or shrubs. Leaves usually evergreen and needle-shaped, awl-shaped, or 

 scale-like. Flowers monoecious or dioecious. Fruit a scaly cone, or sometimes 

 appearing berry-like. 1. pine Family, page 13 



CLASS II 



ANGIOSPERMS. Ovules enclosed in an ovary. 



SUBCLASS I.— MONOCOTYLEDONS. Flowers usually with their parts 

 in threes, never in fives. Leaves usually parallel-veined. Cotyledon 1. 



Flowers enclosed by chaffy bracts. family page 

 Flowers 2-bracted. Leaves 2-ranked. Stem cylin- 

 drical 4. Grass 23 



Flowers 1-bracted. Leaves 3-ranked. Stem trian- 

 gular 5. Sedge 23 



Flowers on a spadix. 



Spadix slender, hairy, and bristly 2. Cat-tail 20 



Spadix fleshy 6. Arum 23 



Flowers not on a spadix. 

 Carpels usually numerous and nearly or entirely 



separate 3. Water-plantain . 21 



Carpels united. 

 Perianth free or adnate only to the base of the ovary'. 



Perianth regular, its parts similar, green, or chaffy 9. Rush 29 



Perianth of 2 sets, one sepal-like, the other petal- 

 like. 

 Style and stigma 1. Petals 3 or 2, soon disap- 

 pearing 7. Spiderwort ... 26 



5 



