608 PART HI. — THE CLASSIFICATION OF PLANTS. 



This tropical order includes the single genus Nepenthes, with about 40 

 species, chiefly inhabiting the Malay Archipelago, but extending to Ceylon, 

 Australia, the Seychelles, and Madagascar : they are mostly climbing shrubs 

 with leaf-tendrils. 



Order 3. Droserace^. Flowers ^, dichlamydeous, generally 

 pentamerous : stamens 5 or 5" : carpels 2-5 ; ovary usually uni- 

 locular with parietal placentae : leaves not pitchered. 



Herbaceous plants, constituting the six genera DionsBa, Aldrovanda, Eoridula, 

 Byblis, Drosera (the Sundew) and Drosophyllum : in Dionasa, Aldrovanda, and 

 Drosophyllum, the gynseceum consists of 5 antipetalous carpels, and the ovary 

 is unilocular ; in Drosera and Eoridula the gynseceum is usually trimerous, the 

 ovary unilocular in the former, trilocular in the latter ; in Byblis it is dimerous 

 and bilocular. The leaf-blade of Dionatja (Venus' fly-trap) and of Aldrovanda 

 is sensitive to touch, the two halves closing sharply along the middle line when 

 irritated : the leaves of the other genera are provided with irritable glandular 

 tentacles (see Figs. 42, 43, p. 66). Aldrovanda {A. vesiculosa) is a rootless, 

 floating water-plant. 



Cohort VI. Guttiferales. Flowers usually cyclic, generally 

 actinomorphic, and pentamerous : sepals usually free, with 

 imbricate aestivation : stamens usually indefinite : gynaeceum 

 syncarpous, ovary uni- or multi-locular : seed exalbuminous. 



Order 1. Hypericace^. Formula usually Jf5, 05, y40 + 5Qo, 

 0^®' ; or ^0 + 3co , (?15)- Sepals sometimes united at the base : sta- 

 mens usually indefinite and polyadelphous ; 

 when in five bundles, the bundles are super- 

 posed on the petals ; this position of the 

 stamens is generally attributed to the sup- 

 pression of an outer whorl of stamens which 

 is indicated by staminodes in species of all 

 the genera : ovary uni- or multi-locular, or 

 Fig. 411. — Diagram of many- chambered ; capsule septicidal ; ovules 

 Hypericum. numerous, anatropous ; placentae parietal or 



axile. Herbs or under-shrubs with decussate entire leaves, which 

 are dotted over with translucent oil-glands ; exstipulate. 



The following are examples of the different relative numbers of staminal 

 bundles and of carpels : — 



Staminal bundles 5, carpels 5 : Hypericum calycinum. 



Staminal bundles 3, carpels 3 : H. humifusum^ hirsutum, montanum, per- 



foratum, undulatHm, barbatum. 

 Staminal bundles 5, carpels 3 : H. Androsamum, hircinum, elatum. 

 Staminal bundles 3, carpels 6 : H. peplidifolium. 

 All these species, except the last (St. John's Worts, or Tutsans), occur wild in 

 Britain. 



