THE POLYPETALOUS ORDERS. 



405 



760. Ord, Sapiadacea; (the Soapberry Family). Trees, shrubs, 

 or climbers, with tendrils, rarely herbs (nearly all tropical and 

 American) ; with alternate and mostly compound leaves. Flowers 

 small, unsymmetrical, usually irregular and polygamous. Calyx 

 of four or five sepals. Petals irregular and often one fewer than 

 the sepals, sometimes wanting. Stamens eight to ten. Ovary two- 

 or three-celled ; the styles or stigmas more or less united. Seeds 

 usually with an aril, destitute of albumen. Embryo coiled ; the 

 cotyledons usually thick and fleshy. Ex. Sapindus (Soapberry, 

 one species of which is indigenous to the southern borders of the 

 United States) ; and Cardiospermum, which is a climbing herb, 

 with a bladdery capsule, often met with in gardens. They are as- 

 tringent and bitter. The fruit of Sapindus is used for soap. The 

 leaves of true Sapindacese are alternate. Inseparably connected 

 with this order is the 



761. Subord, Hippocastanacerc, Trees or shrubs; with opposite 



digitate leaves, without stipules. Fruit roundish, coriaceous, de- 



FIG. 655. Flowering branch of JEsculus Pavia, a species of Buckeye. 656. A flower. 

 657. Flower with the calyx and two of the petals removed. 658. A ground-plan of the flower, 

 showing that its parts are unsymmetrical. 659. Vertical section of an ovary, showing two of 

 the cells with a pair of ovules in each, one ascending, one descending. 660. Cross-section of 

 an ovary. 661. Cross-section of the immature fruit; only one fertile seed; the others abortive. 

 662. The dehiscent fruit. 



