151 



CXXXVII. DROSERACE/E. The Sundew Tribe. 



Droseraceje, Dec. Theorie, 214. (1819) ; Prodr. 1. 317. (1824) ; Lindl. Synops. 38. (1S29). 



Diagnosis. Polypetalous dicotyledons, with definite hypogynous stamens, 

 concrete carpella, a 1 -celled ovarium with narrow parietal placent*, 5 sepals, 

 an erect embryo, and circinate vernation. 



Anomalies. The anthers of Byblis and Roridula open by pores. Verna- 

 tion not circinate in Dion*a. 



Essential Character. — Sepals 5, persistent, equal, with an imbricate [estivation. Petals 

 5, hypogynous. Stamens distinct, withering, either equal in number to the petals and alter- 

 nate with them, or 2, 3, or 4 times as many. Ovarium single ; styles 3-5, either wholly dis- 

 tinct, or slightly connected at the base, bifid or branched. Capsule of 1 or 3 cells, and 3 or 5 

 valve3, which bear the placenta? either in the middle or at the base. Seeds either naked or fur- 

 nished with arillus. Embryo straight, erect, in the axis of a fleshy or cartilaginous albumen. 

 Cotyledons rather thick. — Delicate herbaceous plants, often covered with glands. Leaves alter- 

 nate, with stipulary cilia and a circinate vernation. Peduncles, when young, circinate. 



Affinities. Nearly allied to Violace*, from which their circinate vernation, 

 several styles, minute embryo, and exstipulate leaves, distinguish them. They 

 are also no doubt related to Saxifrage*, to which order it is possible that one 

 of the genera referred to Droseraceae by Decandolle (Romanzovia), actually 

 belongs. The most material circumstance that separates them from Saxifra- 

 ge* is their hypogynous, not perigynous stamens. But when we consider how 

 difficult it frequently is, to determine whether the point of origin of the stamens 

 in Saxifrage* is from the calyx or from below the ovarium, this distinction will 

 cease to have much value. Besides the line of origin of the stamens, these 

 two orders are also distinguished by their vernation and placentation ; but in 

 the latter respect Parnassia among Saxifrage* accords with Droserace* ; and 

 in the former Dion*a among Droserace* accords with Saxifrage*. It is not, 

 however, quite certain that this last-mentioned genus is actually referable to 

 Droserace*, from which it differs remarkably in the structure of its ovarium, in 

 its style, and in its foliage. I am persuaded that Droserace* are fully as nearly 

 related to Saxifrage* as to Violace* ; and this fact shows how much the artifi- 

 cial distribution of orders is at variance with natural affinities. Droserace* 

 are also allied to Sarracenie* : see that order. 



Geography. At the Cape of Good Hope, in South America, North Ameri- 

 ca, New Holland, China, Europe, Madagascar, the East Indies, wherever 

 there are marshes or morasses, these plants are found. Drosophyllum lusita- 

 nicum is remarkable for growing on the barren sands of Portugal. 



Properties. The leaves of Dion*a muscipula are irritable, and collapse 

 when touched. The common Droseras are rather acid, slightly acrid, and, ac- 

 cording to some, poisonous to cattle. The Drosera communis of Brazil is said 

 by M. A. St. Hilaire to be poisonous to sheep. PI. Usuelles, no. 15. 



Examples. Drosera, Drosophyllum. 



CXXXVIII. NEPENTHEiE. The Pitcher-Plant Tribe 



Aristolociiix, § Nepcnthinte, Link Handb. 1. 369. (1829). 



Diagnosis. Apetalous dicotyledons, with a4-celled ovarium, indefinite 

 ovula, a regular imbricated calyx, and pitcher-shaped leaves. 

 Anomalies. The direction of the radicle uncertain. 



