FRUCTUS ECBALLII. 



293 



3-celled and contains numerous oblong seeds lodged in a very hitter 

 succulent pulp. The fruit when ripe separates su<Idcnly from the 

 stalk, and at the same moment the seeds and juice are forcibly expelled 

 from the aperture left by the detached peduncle. This hiteresting 

 phenomenon^ is due to the process of exosmosis, hy which tlie juice of 

 the outer part of the fruit gradually passes through the strong contractile 

 tissue which lines the central cavity, until the pressure becomes so 

 great that the cell gives way at its weakest point. 7'his point is that 

 at which the peduncle is articulated with the fruit; and it is the 

 sudden and powerful contraction of the elastic tissue when relieved 

 from pressure that occasions the violent expulsion of the contents of 

 the central cavity. 



For the preparation of the officinal elaterium, the fruit has to be 

 employed while still somewhat immature, for the simple reason that it 

 would be impossible to gather it so as to retain its all-important juice 

 if left till quite ripe. When it is sliced longitudinally as in making 

 elaterium, some of the juice is expelled by virtue of the endosmotic 

 action already described, as can easily be seen on examining the con- 

 tracted lining of the sliced fruit. 



Pereira observes^ that if the juice of a fruit is received on a plate of 

 glass, it is seen to be nearly colourless and transparent. In a few 

 minutes however, by exposure to the air, it becomes slightly turbid, and 

 small white coagula are formed in it. By slow evaporation, minute 

 rhomboidal crystals make their appearance : these are elaterin. 



Hot, dry weather favours the development of the active principle of 

 the druir.^ 



Micrnsrnnin Rhrn rfnr* 



— The middle layer of the fruit is built up 



vascular 



bundles. The former abound i 

 granules of albuminous matter. 



Chemical 



m 



The experiments of Clutterlnick (1819) 

 proved tliat the active properties of the elaterium plant reside chiefly, 

 though not exclusively, in the juice that surrounds the seeds ; and it is 

 to this juice and to the medicinal product which it yields, that the 

 attention of chemists has been hitherto directed. 



The juice obtained by lightly pressing the sliced fruits is at first 

 greenish and slightly turbid. After having been set aside a few hours, 

 It }iclds a deposit, which has to be collected on calico, rapidly dramed 

 with gentle pressure between layers of bibulous paper and porous bricks, 

 and dried in a warm place. The substance thus obtained is the Elaterium 

 of pharmacy.-' The method recommended by Cluttcrbuck^ involves no 

 pressing. The juice of tlie sliced fruit is saved, and the pulp, scooped 

 ^^^it by the thumb of the operator, is thrown on a sieve and slightly 

 washed with pure water. From these liquors, elaterium is deposited. 



, [ I hare uot yet seeu Yule's paper on the at Mitcham in the very fine summer of 



J^ohiaceaee of Ihis fruit in the l/o«r». of 1868, I was told that the people oeeum 



f'iat. and Physiology, 1877. The struc- in slicing the innts had never suffered so 



ture of the testa of the seed is explained severely from their work as in that year. 



7/4.— F A F 4 There is a genus of CfWUrtttacecE foundea 



; i:frm. of Mat. Mnd. ii. (1853) 1745. by Linnffius also called ^'^If''^- 



Having had to procure elaterium fruits ' loud. Med. Reposdory, xu. (1820} 1. 



