INTRODTJOTIOH. 



-/Corolla regular, the petals equal and similar to each other . 15 



'\Corollairregular .......... 41 



8 /Ovary inferior or adherent, below the insertion of the corolla . 51 



\0vary superior or free, within the tube or base of the corolla . $7 



Polypetala with several free, distinct ovaries or carpels. 



/"Stamens united in a ring or column enclosing the style. 



I Ovaries in a ring round the axis 10 



| Stamens free. Ovaries quite free, each with a distinct style or 

 I stigma, without a central axis 11 



Stamens 5 or 10, shortly united at the base GERANIACE^E (p. 88). 



Stamens indefinite, united in a column . MALVACEAE (p. 84). 



Stamens definite in number (as many, twice, or thrice as many 

 as the petals) 12 



Stamens indefinite (many or rarely few) 13 



Leaves fleshy. Sepals and petals 4 or more CuASSULACEa (p. 158). 



10 



12 



13 



Aquatic plants not fleshy. Sepals and petals 3 each. 



ALISMACE^I (p. 430). 



Leaves without stipules. Stamens inserted on the receptacle 14 

 Leaves with stipules. Stamens on the calyx HOSACEJE (p. 127). 

 Sepals or petals or both 4 or more , RANUNCULACE^E (p. 1). 

 and petals 3 each .... ALISMACE^ (p. 435). 



{ 



16 



Regular Poll/petals with, one free, simple, or compound ovary. 



I More than 10 stamens 16 



\10stamensorfewer 22 



Calyx of 2 distinct sepals. Petals 4 . . PAPAVERACE.E (p. 17). 

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



Stamens about 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 NYMPH^EACE^E (p. 16). 



Petals distinct. Ovary sessile .... LYTHKUM (p. 155). 

 17 { Apparent petals really appendages to the involucre. Ovary ap- 

 parently stalked EUPHORBIA (p. 391). 



1R /Leaves opposite 19 



1 \Leaves alternate 20 



(Sepals 3, with or without 2 small outer ones. Style simple 



19-( CIST ACE M (p. 51). 



( Sepals 5, nearly equal. Styles 3 or5, distinct. HYPERICINE.S: (p. 79). 



(Trees or shrubs. Stamens free 21 

 Herbs. Stamens free ACT^A (p. 14). 

 Herbs or undershrubs. Stamens united in a column round the 

 pistil MALVACEAE (p. 84). 



/"Petals and stamens inserted on the receptacle. Flower-stalk 



2 | winged by an oblong bract .... TILIACE.E (p. 87). 

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



I winged . ROSACEJE (p. 127). 



