ORGANIC MATERIA MEDICA 



PHARMACOGNOSY 



PART I 

 A STUDY OF DRUGS 



CLASSIFICATION 



Drugs may be arranged in several different ways, to suit the aim and 

 convenience of the student. The prominent systems of classification in 

 common use are as follows: 



I. Therapeutical. This system of classification is especially valu- 

 able to the student of medicine. Here the physiological action and thera- 

 peutical application are made most prominent. 



II. Chemical. Classification of organic drugs is not infrequently 

 based upon the character of the constituents. In this way alkaloidal 

 drugs, glucosidal drugs, drugs containing volatile oil, etc., form the sub- 

 groups. Other subgroups of chemical classification are: 



Inorganic Chemicals. To the pharmacist the chemical action, the crys- 

 talline form, the solubility, and other physical properties are of especial 

 value. For mineral substances, therefore, he adopts the classification of 

 the chemist. Some therapeutists, seeing a certain relation between thera- 

 peutical action and chemical constitution, adopt the same method of 

 grouping also for these mineral substances. 



Synthetical Remedies. This class of remedial agents is most difficult 

 to classify in a manner consistent with science, partly because our materia 

 medica is becoming overloaded with proprietary combinations and mix- 

 tures of synthetic medicinal products with various adjuvants to modify 

 their action. These latter have oftentimes certain unscientific names, 

 which give little or no idea of their composition. 



III. Physical. According to this method, drugs having allied phys- 

 ical properties are brought together. Roots, leaves, flowers, fruits, and 

 -seeds form the principal divisions. Under this head two different arrange- 

 ments are present in this volume: (a) Classification into subgroups based 

 upon such prominent features as odor, taste, etc. By this means the 



