RUTACEiE. 



191 



taste, is somewhat soluble in water, and is not acted upon by hydrochloric 

 acid. 



There are several other species of Rue, closely resembling the R. graveo- 

 lens, and which are often cultivated instead of it, the R. chalapensis is only 

 distinguishable by its ciliate petals, and the R. sylvestris is principally recog- 

 nised by the follicles being narrower; both these species are identical with 

 the officinal one in properties, and may without inconvenience be substituted 

 for it. It is stated by Forskal that the R. tuberculata is used by the Arabs 

 to increase the growth of hair on the head and chin. 



Barosma. — Willdenow. 



Sepals 5, united at base, dotted. * Disk at base of calyx with a small rim. Petals 5, 

 unguiculate. Stamens 10, five opposite the petals sterile, petaloid, sessile; the other five 

 longer, subulate; anthers with a gland at apex. Capsules 5, glandular. 



This genus is formed of species formerly belonging to Diosma, and might 

 without impropriety have been retained as a division of it, as the differences 

 are scarcely sufficient to authorize their separation. It is composed of small 

 shrubs, all natives of Southern Africa, where their leaves are used by the 

 Hottentots in the form of powder to sprinkle on their bodies ; they term this 

 powder Bookoo or Buchu. Although all the species possess similar physical 

 properties, only one of them has been recognised as officinal. 



B. crenata, Linn. 

 tary, terminal. 



-Leaves ovate, lanceolate, or obovate, dotted, crenate. Flowers soli- 



Linn., Sp. PL 287; Loddiges, Bot. Col. n.404; Stephenson and Churchill, 

 ii. 121 ; Lindley, Fl. Med. 213. 



Common Names. — Buchu ; Diosma. 



Fig. 102. 



Description. — The plant 

 is perennial, erect, smooth 

 and about two feet in 

 height ; the branches are 

 round or somewhat terete 

 and of a purplish colour. 

 The leaves are opposite, 

 scattered, ovate, acute, of a 

 dark-green colour above, 

 paler beneath, crenated and 

 beset with small transpa- 

 rent punctures, which are 

 most marked near the ere- 

 nations. The flowers are 

 whitish, or of a pale-reddish 

 colour, solitary on short pe- 

 dicels at the ends of short 

 lateral shoots. The calyx 

 has five ovate, acute, per- 

 sistent sepals, and the co- 

 rolla an equal number of 



elliptic, oblong, bluntish petals, which are somewhat spreading. At the base of the co- 

 rolla is a disk or nectary furnished with petaloid processes. The stamens are five, 

 subulate, bearing ovate, incumbent, anthers. The ovary is superior, turbinate, supporting 

 an erect style crowned with a simple stigma. The capsule is ovate, containing a single, 

 oblong black shining seed, with an elastic testa. 



1. Calyx. 



B. crenata. 

 Styles and stigma. 3. Fruit, 

 on leaf. 



4. Seeds 



Dots 



Like the rest of the species it is a native of Southern Africa, where it 



was 



