122 VASCULAR PLANTS. 



Family XC. PolygOnace36. {Of uncertain affinity.) 



Perigonium imbricate in aestivation. Stamens 

 definite, inserted on the base of the perigonium. 

 Ovary superior, originally compound of 2-3 

 carpidia; by abortion, 1-loculate, 1-ovulate; but 

 showing the 2-3 styles of the original carpidia; 

 ovule basilar. Fruit indehiscent. Stems ar- 

 ticulate. Leaves alternate, sheathing. 



1. Rumex, L. 



Perigonium 6-phyllous, 2-seriate ; 3 inner seg- 

 ments larger and more petaloid. Stamens 6, 

 in pairs opposite the outer sepals. Styles 3 

 with penicillate stigmas. Fruit a 3-cornered 

 akene enclosed in the 3 inner sepals, forming a 

 spurious capsule. 



. % . flowers racemose. 



2. Polygonum, L. 



Perigonium 5, sometimes 4-phyllous. Sta- 

 mens 3 — 8, single or in pairs opposite to the 

 sepals. Styles 3, sometimes 2; stigmas capitu- 

 late. Fruit a 3-cornered or lenticular akene en- 

 closed in the persistent perigonium. 



. U . ^ . flowers often colored . 



3. Eriogonum, Michx. 



Involucre go -flowered, campanulate, slightly 

 angulate, 6-dentate. Flowers § pedicillate, 

 exserted, seated on a receptacle with scarious 



