658 



BOTANY 



PART II 



OFFICIAL. Rhamnus purshianus yields CASCARA SAGRADA or RHAMNI 



PURSHIANI CORTEX. 



Family 2. Vitaceae (Figs. 688, 689). The genera Vitis, Ampelopsis, and 

 Parthenocissus in the northern hemisphere and the tropical genus Cissus belong 

 here. Vitis vinifera, the Grape Vine, is a cultivated plant with numerous races 

 and varieties. The tendrils correspond to shoots and stand opposite to the 

 leaves ; they are at first terminal, but become displaced to one side by the develop- 

 ment of the axillary shoot. The inflorescence is a panicle taking the place of a 

 tendril ; intermediate forms between inflorescences and tendrils are of frequent 

 occurrence. Calyx only represented by a small rim ; the pentamerous corolla, 

 with the petals united by their tips, is thrown off when the flower opens. Raisins 

 are obtained from Vitis vinifera. Currants are the seedless fruits of Vitis vinifera, 



FIG. 088. Vitis vinifera. Opening 

 flower, a, Calyx ; b, corolla ; c, 

 disc ; d, stamens ; e, ovary (mag- 

 nified). (After BERG and SCHMIDT.) 



FIG. 689. Floral diagram of Ampelopsis 

 hederacea. (After EICHLER.) 



var. apyrena. Species of Parthenocissus distributed in North America and Asia 

 go by the name of Wild Vines ; some of them have tendrils with adhesive discs 

 (Fig. 210). 



Order 18. Rosiflorae 



The cyclic flowers are in other respects similar to those of the 

 Polycarpicae ; the connection of the Rosaceae with the Calycanthaceae 

 is particularly close. The single carpel in the Pruneae and the 

 dorsiventral flowers of the Chrysobalaneae lead on to the Leguminosae. 



The order includes plants of very diverse form and construction 

 with alternate leaves. The flowers are almost always actinomorphic 

 with the members arranged in whorls ; they have five, ten or 

 numerous stamens and carpels, the pistil is as a rule apocarpous. The 

 large part played by the floral axis in the construction of the flower 

 and fruit is characteristic. K5, C5, A5-oo , Gl-oo . 



Family 1. Crassulaceae. Succulent herbs (cf. p. 174) or under-shrubs with 

 cymose inflorescences. Sedum (Fig. 690) with pentamerous flowers ; there are a 

 number of British species. Sempenrivum, flowers with from six to an indefinite 

 number of members in the whorls ; S. tectorum. Bryophyllum with tetramerous 

 flowers, noteworthy on account of the abundant formation of buds in the indenta- 

 tions of the margin of the leaf. Crassula ; South African forms mimic stones by 

 their globular form ( 23 ). 



