Bawden, Movements of the Neurone. 247 



subject from the standpoint of the histology of the cortex. Another 

 paper (22) the following year (1897) by the same author discussed 

 again the function of the neuroglia. 



In 1898 appeared the second and more elaborate paper of Duval 

 (32) which covers about the same ground as Deyber's thesis. Duval 

 says than when he suggested the hypothesis in his former paper the 

 idea was already in the air, so to speak, ready to be formulated and he 

 was the one to strike it off. At that time, he says, he was not aware of 

 the previously published articles of Rabl-Riickhard (1890), of Tanzi 

 (1893), of Lepine (1894).^ The doctrine has now passed, he says, 

 from the stage of an hypothesis to that of an anatomically demonstrated 

 fact. He then refers to the work of his pupils. Two of them made 

 the theory the subject of their inaugural theses. Pupin treats it on the 

 theoretical side, while Deyber's thesis is an exposition of the researches 

 of the two investigators, Demoor and Stefanowska. Still more re- 

 cently another of his pupils, Manouelian, carried through researches 

 in his laboratory which, he says, are clearly demonstrative of the truth 

 of his doctrine. These researches will be taken up below. Duval 

 cites van Gehuchten in support of his theory that there are cer- 

 tain regions, or a series of regions, where the peripheral articulate with 

 the central neurones. The nuclei of the columns of Goll and of Bur- 

 dach (posterior pyramids) in the medulla represent one of the more 

 important of these regions. Here the peripheral pathways or neurones 

 connect with the central, the axones of the latter passing to the cere- 

 bral cortex where they articulate with the dendrites of the pyramidal 

 cells or psychical neurones. In sleep reflexes do not disappear. Con- 

 sequently there is no interruption of the connections of the neurones 

 which make up the reflex arc. The interruption in the case of sleep 

 takes place either at the point of articulation of the peripheral with the 

 central neurones or at the point of articulation of the central with the 

 psychical neurones. But even these are not always completely inter- 

 rupted as shown in the phenomena of dreams. Duval divides his proof, 

 as does Deyber, into two main divisions, proofs by analogy and direct 

 proofs. The proofs by analogy are the supposed amoeboid movements 

 of the retinal elements on the one hand, and the supposed amoeboid 

 movents of the olfactory cilia on the other. Deyber brings in also 

 some collateral phenomena from other tissues. The direct proofs are 

 found in the researches of Demoor, Stefanowska, Manouelian, and 

 Odier. These will be taken up below in connection with the criticism 



He did mention Tanzi, however. 



