158 RHAMNACE^. 



botany and materia medica of the 16th century. Syrup of buckthorn 

 first appeared in the London Pharmacopoeia of 1650; it was aromatized 

 by means of aniseed, cinnamon, mastich and nutmeg. 



Description — The fruits, which are only used in the fresh state, are 

 small, juicy, spherical drupes the size of a pea, black and shining, 

 bearing on the summit the remnants of the style, and supported below 

 by a slender stalk expanded into a disc-like receptacle. Before ripening 

 the fruit is green and distinctly 4-lobed, afterwards smooth and plump. 

 It contains 4 one-seeded nuts ^ meeting at right angles in the middle. 

 The seed is erect with a broad furrow on the back: in transverse section 

 the albumen and cotyledons are seen to be curved into a horse-shoe 

 form with the ends directed outwards. 



The fresh juice is green, has an acid reaction and a sweetish, after- 

 wards disagreeably bitter taste, and repulsive odour. It is coloured 

 dingy green by ferric chloride, yellow by alkalis, red by acids. Accord- 

 ing to Umney '^ it should have a sp. gr. of 1070 to 1075, but is seldom 

 sold pure. By keeping the juice gradually turns red. 



Microscopic Structure — The epidermis consists of small tabular 

 cells, followed by a row of large cubic cells and then by several layers 

 of tangentially-extended cells rich in chlorophyll. This thick epicarp 

 passes into the loose thin-walled and large-celled sarocarp. Besides 

 chlorophyll it exhibits numerous cells each containing a kind of sac, 

 which may be squeezed out of the cell. These sacs are violet, turning 

 blue with alkalis. Similar, yet much more conspicuous bodies occur 

 also in the pulp of the Locust Bean (Ceratonia Siliqua L.). 



Chemical Composition — The berries of buckthorn and other 

 species of Rhmnnus contain interesting colouring matters, which have 

 been the subject of much chemical research and controversy. Winckler 

 in 1849 extracted from the juice Rhainnocathartin, a yellowish un- 

 crystallizable bitter substance, soluble in water but not in ether. 

 Alkalis colour it golden yellow; perchloride of iron, dark greenish 

 brown. 



In 1840 Fleury, a pharmacien of Pontoise, discovered in buckthorn 

 juice a yellow substance forming cauliflower-like crystals to which he 

 gave the name of Bhamnine. This body has been recently studied by 

 Lefort,* who identified it with the Rhamnetine of Galletly (1858) and 

 the Chrysorhamnine of SchUtzenberger and Berteche (1865). Though 

 obtainable from the berries of all kinds of Rhanmus used in dyeing 

 (including the common buckthorn), it is got most easily and 

 abundantly from Persian Berries. When pure, and crystallized from 

 absolute alcohol, it is described as forming minute yellow translucent 

 tables. It is scarcely soluble in cold water, though colouring it pale 

 yellow ; is soluble in hot alcohol, insoluble in ether or bisulphide of 

 carbon. It is veiy soluble in caustic alkalis, forming uncrystallizable 

 reddish-yellow solutions. From alkaline solutions it is precipitated by 

 a mineral acid in the form of a glutinous magma resembling hydrated 

 silica. Lefort assigns to it the formula C^H^'^O' -f- 2H'0. 



^ In Rh. Franrjula L., the other British ^ bur les fira'mes dcs Kerprunn linctoriavx. 



species, the fruit has 2 nuts. — Jotim. de Pharm. iv. (1866) 420. — See 



- Pharm. Journ. Nov. 23 (1872) 404, and also the investigations of Liebermann and 



July 11 (1874) 21. Hurmann. 1879. 



