VASCULAR PLANTS. 43 



4. Heterocodon, Nutt. 



Early flowers cleistogamic ; later ones ex- 

 panding. Calyx turbinate. Corolla cainpanu- 

 late. Capsule membranaceous, turbinate, open- 

 ing irregularly. 



0. flowers blue. 



Family III. Cucurbitaceae . 



Monoecious or dioecious. $ : stamens 5, tri- 

 adelphous; loculi of anthers contorted, flex- 

 uous. ? : ovary 2 — 5-locular, placentae parie- 

 tal; style 1, stigmas 3. " 



1. Megarrhiza, Torrey. 



Monoecious. $ flowers racemose. $ flow- 

 ers single from the axil of the £ raceme. Limb 

 of calyx, minutely 5-dentata. Corolla rotate, 

 deeply 5-lobed. Fruit a berry. Seeds large, 

 globose. 



It. root large; stem climbing by tendrils; 

 flowers greenish white. 



ORDER H. RUBIALES. 



Epigynous. Stamens inserted into the corolla, 

 alternate with its lobes. Leaves opposite. 



Family IV. Dipsaceae. 



Stipules none. Flowers in involucrate heads : 

 single ones protected by a double, involucellate 



