538 



PART IV. CLASSIFICATION. 



Tribe 9. CakilinecK. Silicula two-jointed. This tribe contains the 

 genera Cakile, the Sea-Rocket, and Crambe, the Sea-Kale. 



Tribe 10. RaphanetK. Silicula more or less moniliform. Raphanm sati- 

 vus is the Radish ; It. Baphanistrum, the wild Radish or White Charlock, 

 is a common weed. 



Order 4. CISTACE.E. Flowers usually actinomorphic and penta- 

 merous : the two external of the five sepals are generally smaller, 

 aud sometimes they are absent : stamens numerous, in consequence 

 of multiplication : carpels 3-10, forming a uni- or multilocular 

 ovary ; ovules orthotropous ; seed with endosperm. Trees or shrubs 

 with generally opposite stipulate leaves. 



Cistus has 5-10 carpels forming a chambered or completely mutilocular 

 ovary. Cistus ladaniferus, creticue, ^.nd other species, grow in the south of 

 Europe : a balsam is derived from them. Helianthemum has a unilocular 



trimerous ovary : Helian- 

 themum vulgare, the Bock 

 Hose, is an under -shrub 

 which grows wild on dry 

 soils. 



Order 5. VIOLACELE. 

 Floral formula 7i5, Co, 

 A5, G { ~ : flowers always 

 borne laterally : ovules 

 anatropous : fruit a Iccu- 

 licidal capsule (Fig. 349 

 (7) : seed with endo- 

 sperm. The indigenous 

 species have irregular 

 dorsiventral flowers ; the 

 anterior inferior petal is 

 prolonged into a hollow spur (Fig. 349 A cs) in which the nectar 

 secreted by the spur-like appendages of the two lower stamens 

 collects (Fig. 349 Afs). The sepals are produced at the base (Fig. 

 349 A Is}. 



Viola is the Violet, Pansy, or Heart's-ease : many species, as V. odorata, 

 the Sweet Violet, have only an underground stem which bears cataplryll- 

 ary leaves, and which throws up petiolate foliage-leaves, and bracteolate 

 peduncles each bearing a single flower : V. odorata has runners, but hirta 

 and collina have none : in others, as V. canina, the Dog-Violet, the main 

 stem is above ground and bears the foliage-leaves : in V. mirabilis these 

 two forms are so combined that, in the spring, flowers are developed from 

 the rhizome which have large blue petals but are always sterile ; it is not 



Fis. 349 Viola tricolor. A Longitudinal section of 

 flower: v bracteole on the peduncle; I sepals; Is ap- 

 pendage; c petals; cs spur of the lower petals ; j't 

 glandular appendage of the lower stamens ; a an- 

 thers (after Sachs). B Ripe fruit ; fc calyx. C After 

 Oehiscence; p parietal placenta; steeds. (Mag.) 



