RUTACEiE. 467 



to the fresh cut surface of a potato, gives rise to a blue colour. Both 

 the wood and the resin are used medicinally on account of their 

 stimulant diaphoretic properties. In decoction and tincture they are 

 administered in cutaneous and syphilitic diseases. Ouaiacum sanctum 

 from Mexico and the Bahamas also supplies Guaiac resin, and is 

 sometimes used mediciually on the continent. Tribulus terrestris is a 

 prickly plant which grows iu the East, and is found in Palestin*. 

 Some suppose that the Hebrew word ITn, dardar, translated thistle 

 iu the Old Testament, and rgl^oXog, translated thistle in the New 

 Testament, refers to this plant (figs. 534, 535, p. 300). 



Order 52.^ — RuTACEiE, the Rue Family. (Polypet. Hypog.) See 

 figs. 632, 633, p. 364. Calyx having 4-5 segments, with an imbricated 

 sestivation. Petals alternate with the divisions of the calyx, distinct, 

 or cohering below into a spurious gamopetalous corolla, rarely wanting; 

 aestivation either contorted or valvate. Stamens equal in number to 

 the petals (fig. 632, p. 364), or twice or thrice as many (rarely fewer 

 by abortion or non-development) (fig. 633, p. 364), usually hypogy- 

 nous, but in some instances perigynous. Between the stamens and 

 ovary there is a more or less complete cup-shaped disk, which is either 

 free or united to the calyx. Ovary sessile or supported on a gyno- 

 phore (fig. 416, p. 239), its carpels equal to the petals in number or 

 fewer; ovules 2, rarely 4 or more in each carpel; styles adherent 

 above (fig. 416, p. 239); stigma simple or dUated. Fruit capsular, 

 its parts either combined completely or partially ; seeds solitary or in 

 pairs, albuminous or exalbuminous ; embryo with a superior radicle. 

 — Trees or shrubs, with exstipulate, opposite, or alternate leaves, 

 usually covered vpith pellucid resinous dots (figs. 92, p. 35 ; 95, p. 36), 

 and hermaphrodite flowers. The order has been subdivided into two 

 sub-orders : — 1. Euteae, with albuminous seeds, and the fruit with 

 sarcocarp and endocarp combined. 2. Diosmese, with exalbuminous 

 seeds, and a 2-valved endocarp, which dehisces at the base, and when 

 the fruit is ripe separates from a 2-valved sarcocarp. Kutese are 

 found chiefly in the southern part of the temperate zone, as in the 

 south of Europe, while Diosmese abound at the Cape of Good Hope and 

 in Australia. Authors mention 44 genera and 430 species. Examples — 

 Euta, Dictamnus, Diosma, Barosma, Correa, Boronia, Zieria, Pilocarpus. 



The plants are remarkable for their peculiar odour, which is very 

 powerful and penetrating. Many have antispasmodic properties, 

 while others are bitter, and act as febrifuges and tonics. The leaves 

 and unripe fruit of Ruta graveolens, common or garden Rue, are used 

 in medicine as stimulant, antispasmodic, anthelmintic, and emmen- 

 agogue. They emit when bruised a strong and peculiar oppressive 

 odour," and have a bitter and acrid taste. By distillation with water 

 they yield a yellow acrid volatile oil, which is their active constituent. 

 The leaves of various species of Barosma, especially B. crenulata, 



