DISEASES OF THE NERVOUS SYSTEM 91 



upon the brain (cerebralics, encephalics), upon the spinal cord 

 (spinalics), and upon the peripheral nerves (peripheric nervines). 

 Besides this anatomical division, the classification based upon 

 physiological principles is of special practical importance in thera- 

 peutics; according to action, there are drugs which are stimulating 

 (excitants) and others which are quieting (sedatives) to the nerv- 

 ous structures. Finally, there may be a combination of the two 

 methods of classification. In this way the following subdivisions 

 have been formed: 



I. Cerebralics. These are again subdivided into drugs which 

 act upon the cerebrum, upon the medulla oblongata and upon the 

 twelve cranial nerves. Those drugs which have a relation to the 

 cerebellum, e.g., alcohol and aspidium, are of no special practical 

 consideration in this connection. 



1. The drugs acting upon the cerebrum are divided according 

 to the location and character of their action into the following 

 groups : 



(a) Excitants to the cortical psychic centres: alcohol, ether, 



caffeine, nicotine, cocaine and apomorphine. 



(b) Excitants to the motor centres: atropine, camphor, picro- 



toxin and lead salts. 



(c) Sedatives for both kinds of centres: potassium bromide 



and chloral hydrate. 



(d) Hypnotics (drugs that produce sleep): morphine, chloral 



hydrate, sulphonal, trional, veronal, medinal, isopral 

 and adalin. 



(e) Narcotics and anaesthetics in the restricted sense: chloro- 



form, ether and chloral. 



2. For the medulla oblongata there are: 



(a) Excitants in general: veratrine, atropine, hyoscine (scopo- 



lamine), caffeine, strychnine, camphor and ammonium 

 salts. 



(b) Sedatives in general: morphine, potassium bromide and 



chloral hydrate. 



(c) Excitants to the respiratory centre: atropine, hyoscine 



(scopolamine) and strychnine. 



