15 



16-! 



lx INTRODUCTION. 



Regular Polypetals with one free, simple, or compound ovary. 



{More than 10 stamens 16 

 10 stamens or fewer 22 



Calyx of 2 distinct sepals. Petals 4 Poppy Fam. (p. 28.) 



Calyx of one piece, with 5 or more teeth. Petals 5 or 6. Stamens 



abont 12 17 



Calyx of 3 to 5 sepals or lobes. Petals 5. Stamens numerous . . 18 

 Calyx of several sepals. Petals and stamens numerous. Aquatic 



plants Waterlily Fam. (p. 26.) 



" Petals distinct. Ovary sessile Lythrum Gen. (p. 287.) 



17 K Apparent petals really appendages to the involucre. Ovary appa- 



L rently stalked Spurge Gen. (p. 727.) 



, £ / Leaves opposite 19 



1 Leaves alternate 20 



f Sepals 3, with or without two small outer ones. Style simple. 

 19 \ Cistus Fam. (p. 91.) 



^Sepals 5, nearly equal. Styles 3 or 5, distinct. Hypericum Fam. (p. 139.) 



(Trees or shrubs. Stamens free 21 

 Herbs. Stamens free Baneberry Gen. (p. 24.) 

 Herbs or undershrubs. Stamens united in a column round the pistil. 

 , Mallow Fam. (p. 151.) 

 {Petals and stamens inserted on the receptacle. Flower-stalk winged 

 by an oblong bract Lime Fam. (p. 157.) 

 Petals and stamens inserted on the calyx. Flower-stalk not winged. 

 Rose Fam. (p. 234.) 



22 f Leaves opposite 23 



\ Leaves alternate, or radical, or none 30 



9Q f Trees or shrubs 24 



^1 Herbs • 25 



f Stamens 2. Leaves pinnate Ash Gen. (p. 554.) 



24 \ Stamens 4 or 5. Leaves ovate, toothed . . Celastrus Fam. (p. 177.) 



[_ Stamens about 8. Leaves broadly lobed or angular. Maple Gen. (p. 175.) 

 f Petals inserted on the tubular calyx, near the top. 



25 \ Lythrum Fam. (p. 287.) 

 (^Petals inserted within the base of the calyx "26 



2fi f Leaves divided, cut, or toothed Geranium Fam. (p. 158.) 



\ Leaves quite entire 27 



{Capsule one-celled, with a central placenta and several seeds. 

 Pink Fam. (p. 100.) 

 Capsule with a single seed Paronychia Fam. (p. 685.) 

 Capsule and ovary divided into several cells 28 



{Petals 3 or 4, with twice as many stamens. Flowers very minute. 

 Elatine Gen. (p. 138.) 

 Petals 4 or 5. Stamens the same, or rarely one or 2 additional 

 ones 29 



f Calyx tubular, five-toothed Frankenia Gen. (p. 100.) 



29 \ Calyx many-toothed. Flowers very small . . Radiola Gen. (p. 151.) 



L Sepals 5, quite free Cathartic Flax (p. 150.) 



[ Trees or shrubs 31 



qq J Low procumbent heath-like undershrub, with 3 petals and stamens. 



| Crowberry Gen. (p. 738.) 



l^Herbs rarely slightly woody at the base 34 



("Petals and stamens 6. Berry one- or two-seeded. 

 31 \ Barberry Gen. (p. 26.) 

 ^Petals 4 or 5. Stamens as many, or twice as many 32 



