640 



PART III. — THE CLASSIFICATION OF PLANTS. 



Tribe 5. Rihesiece. Flowers epigynous, incompletely actinomorphic, penta- 

 merous : stamens five, opposite to the sepals ; carpels usually two, usually 

 median, sometimes lateral (Fig. 324B) : fruit a berry : leaves scattered : inflo- 

 rescence racemose. Shrubs. 



Several species of Ribes, the Currant, are cultivated : JR. rubrnm is the Eed 

 Currant; R. nigrum, the BlsLck Currant; R. Grossiilaria, the Gooseberry: the 

 spines of the last species are developed from the pulvinus. 



Various species of Escallonia are cultivated as ornamental floweriog shrnbs. 



Order 2. Ckassulace^. Formula Kn, Cn, \ Jn-f n, Gn, where 

 n = 3 — 30: flowers actinomorphic, perigynous or hjpogynous, 

 with two (rarely one) whorls of stamens : gynseceum, generally 

 completely apocarpous ; carpels opposite to the petals, with a scale 

 (disc), external to each carpel : ovules numerous, marginal : fruit 



Fig. 441.— Flower of Bibes (mag.): 8 Fig. 412.— Flower of Sedum aci<;(x 3). 



pedicel ; fc calyx ; c corolla ; st stamens ; 

 b disc ; g styles. 



a follicle : seed with endosperm : inflorescence usually cymose. 

 Plants with entire fleshy leaves, arranged spirally, often in rosettes. 



The genus Sedum has usually pentamerous flowers ; Sednni acre, the Stone- 

 crop, is common on walls and rocks ; S. Rhodiola has dioecious flowers (see 

 Fig. 318). S. Telephium, the Orpine and others are common. The genus Sem- 

 pervivumhas at least 6-merou8 flowers; S. Tectontm, the Houseleek, and other 

 species, as also species of Echeveria, Crassula, etc., are frequently cultivated. 

 Tillsea has usually tetramerous flowers without the hypocarpellary scales. 



Order 3. Cephalotace^. Flowers apetalous, perigynous, 6- 

 merous : stamens in two whorls : gynseceum of six apocarpous 

 carpels, each containing a single basal ovule. 



This order consists of the Australian genus Cephalotus, with the single 

 species C. follicularis : the lower of the tuft of radical leaves are pitchered and 

 have lids. 



Order 4. Pittosporace^. Flowers hypogynous : stamens five, 

 antisepalous : carpels 2-5, ovary syncarpous, uni- or multi-locular, 



