Meyer, Data of Modem Neurology. 309 



From all that was said from the clinical point of view we 

 need charts of the sensory surfaces of man giving : 



1. The districts of distribution of the nerves after they 

 emerge from the plexus, i. e. the really peripheral branches. 



2. The distribution of parts of the plexus. 



3. The distribution of the posterior roots. 



4. The distribution from the cross-lesions. 



5. The distribution from lesions of the fillet, and the 

 known clinical types of cortical foci. 



6. Types of distribution in hysteria. 



It is evident that the data for all these charts are partly 

 widely scattered, and partly not available yet. But the work 

 of the last years has filled many gaps and if more people knew 

 where the gaps are, more would keep their eyes open. 



On the side of motor observations we should return to 

 Duchenne de Boulogne. Muscles and muscle-groups should be 

 presented in the charts. 



1. The muscles depending on definite peripheral nerves. 



2. The muscles depending on parts of the plexus. 



3. The muscles fed by each anterior root (segmental dis- 

 tribution). 



4. Types of involvement of the cerebral efferent tract 

 (pyramids), and of cortical 'areas.' 



5. Types of segmental and supra-segmental lesions — cross- 

 lesions of the tube. 



These charts must naturally be the result of many clean 

 observations. They will become the expression of definite clin- 

 ical data comparable with anatomical data in a dissection of the 

 anatomical substrata, after the plan given in the charts of the 

 general and minute architecture. 



To sum up: Let us remember once forever that the phrase 

 * Ubi est morbus ' does not mean ' which symptom to which 

 neurone.' We have, for our diagnostic reasoning, three really 

 independent series of facts, each series complete in itself; a 

 motor (objective) series, a sensory (subjective) series and an 

 anatomical series of data. We have to blend these together to 

 get. the picture of the disease. The motor series, and the sen- 



