270 EOSACEiE. 



double row of closely-packed seeds, 8 to 14 in number, cohering by 

 a soft mucilaginous membrane with which each is surrounded. By 

 drying, they become hard, but remain agglutinated as in the cell. 

 The seeds have an ovoid or obconic form, rather flattened and 

 3-sided by mutual pressure. From the hilum at the lower pointed 

 end, the raphe passes as a straight ridge to the opposite extremity, 

 which is slightly beaked and marked with a scar indicating the 

 chalaza. The edge opposite the raphe is more or less arched accord- 

 ing to the position of the individual seed in the cell. The testa 

 encloses two thick, veined cotyledons, having a straight radicle 

 directed towards the hilum. 



Quince seeds have a mahogany-brown colour, and when unbroken 

 a simply mucilaginous taste. But the kernels have the odour and taste 

 of bitter almonds, and evolve hydrocyanic acid when comminuted and 

 mixed with water. 



Microscopic Structure — The epidermis of the seed consists of 

 one row of cylindrical cells, the walls of which swell up in the pre- 

 sence of water and are dissolved, so as to yield an abundance of 

 mucilage. This process can easily be observed, if thin sections of the 

 seed are examined under glycerine, which acts on them but slowly. 



Chemical Composition — The mucilage of the epidermis is pre- 

 sent in such quantity, that the seed easily coagulates forty times its 

 weight of water. By complete exhaustion, the seeds afford about 

 20 per cent, of dry mucilage, containing considerable quantities of 

 calcium salts and albuminous matter, of which it is not easily 

 deprived. When treated with nitric acid, it yields oxalic acid. 

 After a short treatment with strong sulphuric acid it is coloured 

 blue by iodine. Tollens and Kirchner (1874) assign to it the formula 

 Qi8jj28Qi4^ regarding it as a compound of gum, C^'H^O^", and cellulose, 

 Q6jjioQ5^ less one molecule of water. 



Quince mucilage has but little adhesive power, and is not thickened 

 by borax. That portion of it which is really in a state of solution and 

 which may be separated by filtration, is precipitable by metallic salts or 

 by alcohol. The latter precipitate after it has been dried is no longer 

 dissolved by water either cold or warm. Quince mucilage is, on the 

 whole, to be regarded as a soluble modification of cellulose. 



The seeds on distillation with water aflford a little hydrocyanic acid, 

 and, probably, bitter almond oil. 



Commerce — Quince seeds reach England from Hamburg ; and are 

 frequently quoted in Hamburg price-currents as Russian ; they are also 

 brought from the south of France and from the Cape of Good Hope. 

 They are largely imported into India from the Persian Gulf, and by 

 land from Afghanistan. 



Uses — A decoction of quince seeds is occasionally used as a de- 

 mulcent external application in skin complaints. It is also sometimes 

 added to eye-lotions. Quince seeds are in general use among the natives 

 of India as a demulcent tonic and restorative. They have been foimd 

 useful by Europeans in dysentery. 



