362 PHYSIOLOGY AT THE FARM. 



Paullinia sorbilis is the guarana plant. The seeds of this 

 plant, after being dried and deprived of their white aril, are 

 pounded and kneaded into a dough, which is then made up 

 into balls. This substance supplies an important beverage, and 

 even bread, to the inhabitants of large districts of country in 

 South America. Its principle, guaranine, appears to be identi- 

 cal with theine. 



Sapindus senegalensis has much-prized berries. Sapindus 

 esculentus has a fleshy fruit in great esteem. 



Schmidelia edulis has fruit eaten in Brazil. 

 , Rhizobolacece, Suwarrow Nut order. Caryocar lutyrosum, 

 or Pekea tuberculosa, is a gigantic tree of Demerara, produc- 

 ing the souari, suwarrow, or surahwa nuts, the kernels of which 

 are esteemed the most agreeable of all the nut kind.* An 

 oil is extracted from them not inferior to that of the olive. 



Vitacece or Ampelidece, Vine order. Vitis vinifera, the 

 grape-vine. Eaisins ; currants. The finest raisins are the 

 muscatel. The sultana raisin is seedless. Currant is a cor- 

 ruption of Corinthian grape. Their dietetic use is apparently 

 connected with their acid character. 



Geraniacece, Cranesbill order. Pelargonium triste has 

 tubers which are eaten at the Cape of Good Hope. 

 . Linacece, Flax order. Linum usitatissimum is the culti- 

 vated flax. The cake left after the expression of linseed-oil 

 from the seeds is the oilcake of agriculture. 



The seeds of the flax have long been known to be highly 

 nutritious. The whole seed boiled soft, together with the 

 water in which it has been boiled, is given in many districts 

 as a cordial drink to cows after calving, and as a tonic to pro- 

 mote recovery after an illness. But even after boiling, owing 

 to the strength of its envelope, the seed is apt to pass through 

 the digestive organs of ruminating animals unaltered. To 



* Balfour, Class-Book of Botany,' p. 781. 



