TASTE. 113 



flowers upon Polemonium cseruleum ; and the circum- 

 stance of different coloured flowers existing upon the 

 same plant is not now considered, as it was formerly, of 

 very rare occurrence. 



152. Taste. The sweetness, acidity, acridity, etc., of 

 plants are derived from substances we have already 

 mentioned, such as starch, sugar, acids, and resins ; but 

 whether any particular flavour is pleasant or disagree- 

 able, will depend much upon the person perceiving 

 it, though all may agree as to any plant having a 

 powerful or only a weak flavour. In some the alkaloids 

 have a very strong taste, as in Stychnia nux vomica. 

 Assafcetida or Devil's Dung, Aloes, Quassia, etc., are other 

 instances of powerful vegetable flavours. Some persons 

 will be more apt to discover one particular flavour from 

 another, though both may exist in the same plant, and 

 the one they think predominates may be looked upon by 

 other persons as existing in a less marked degree than 

 the other which they will first notice. Some plants, 

 however, obtain for themselves a universal disgust 

 or dislike when once they have been employed. The 

 twigs and stems of Glycyrrhiza glabra every child gets 

 hold of and sucks as long as there is the least possible use 

 in sucking ; whilst at the mere mention of some of 

 the Caladia in the West Indies fear will ensue. So 

 acid is the Caladium seguinum, that when a small 

 piece is chewed, it paralyses the muscles of the mouth r 

 fauces, causes the tongue to swell, and deprives the suf- 

 ferer of the faculty of speech ; and occasionally, says 

 Merat, the lips of the negroes are wetted with the 

 Caladium arborescens as a punishment for slight misde- 

 meanours. 



153. Odour. The odour of plants is intimately de- 

 pendent upon the existence of essential oil ; and the 

 more strong and volatile these oils are, so is the odour 

 more powerful and more easily elicited. 



154. The odours given out by plants vary in intensity 

 according to climate, many plants indigenous to Europe 

 give out more powerful ones when growing in the tropics ; 



