138 



COLLEGE BOTANY 



derivatives should never be used except when prescribed by 

 a physician, 



(e) Nicotine of tobacco is one of the most violent poisons. 

 However, it is used for its effects on the nervous system more 

 than any other drug. It has been estimated that more than 

 800,000,000 people make use of it for this purpose. Its effects 

 vary greatly with the age, nervous temperament and habits of 

 the user. However, it is very generally conceded by all who 



have made a scien- 



J"^ ^^-^ tine study of the sub- 



f \^^^T" *^^= ^ jeet -that it is always 

 ^ ^ ^^/ : injurious. 



(/) Atropine of 

 the belladonna plant 

 is used to some ex- 

 tent in medicina 



(g) Quinine 

 from the cinchona tree is very extensively used in medicine. 



(h) Strychnine from the mix vomica tree is a most violent 

 poison which is used to some extent in medicine. 



The glucosides are probably formed by the protoplasm. They 

 are compounds of glucose and other substances and may be either 

 nitrogenous or non-nitrogenous. They are bitter to the taste 

 and some of them undoubtedly serve as reserve food materials. 

 They are very numerous and among the most important are: 

 (a) amygdalin of the bitter almond, (&) solanin alkaloid of the 

 Solanacese, (c) salacin of the willows, (d) coniferm of the 

 Conifers and (e) digitalin of the Digitalis or Foxglove. 



The pigments are the coloring products found in the cell sap 

 or in the chloroplasts and chromoplasts. Their origin and their 



FIG. 95. Sphsero-crystals of inulin. 



