246 Journal of Comparative Neurology. 



end to the muscarin stand-still." That is, the latter poisons, muscarin 

 and atropin, act on the dendritic branches of the nerve cells rather 

 than on the cell bodies themselves, thus, as the author says, " giving 

 firmer ground for the view that muscarin and atropin exert their effect 

 on the heart, so far as the effect is nervous, by acting on the nerve end- 

 ings in the muscles" (p. 279-280). 



A. von KoUiker {52) in March, 1895, publishes a critique of the 

 hypothesis of Rabl-Riickhard and Duval, in which he contends that 

 such amoeboid movements of the nerve cell have never been observed, 

 and that such a theory is incompatible with the doctrine of the fibrillar 

 structure of the nerve elements. 



About the same time Ramon y Cajal (18 and 19) published papers 

 locating the amoeboid movements in the neuroglia cells, thus admitting 

 the possibility of variations in the structure of the cortex, but not grant- 

 ing amoeboid properties to the nerve cells as such. 



A paper appeared also during this year (1895) by Renaut (91) on 

 the articulation of the neurones. 



During 1895-1896 we have two papers by Demoor (26 and 27). 

 He had previously touched on the subject in a paper (24) in 1893, and 

 in a preliminary report (25) in 1895. I^ the research reported in the 

 first paper mentioned (26), dogs were first subjected to the influence 

 of morphine, chloral and chloroform. The histological changes ob- 

 served in the nerve cells were the disappearance of the gemmules and 

 the moniliform appearance of the dendrites. In a subsequent paper 

 (27) Demoor applies these observations to the theory of sleep in much 

 the same way as Duval, though he employs the term ' ' morphological 

 plasticity " instead of Duval's term " amoeboid movement." He cites 

 researches on changes in functional variation and fatigue by Flesch, 

 Magini, Vas, Lambert, Hodge, and Lugaro ; but he lays particular 

 stress on the researches of Mann and of Pergens. As these papers 

 will be referred to again, no further notice will be taken of them here. 

 Demoor points out Duval's misuse of Wiedersheim's observations 

 and make a reply to Kolliker's criticism of the theory of amoeboid 

 movements. 



In 1896 appeared the thesis of Ch. Pupin (83) which the present 

 writer has not had the opportunity of consulting. Duval says, however 

 that Pupin (Pupin was his pupil) takes up the question chiefly on the 

 theoretical side, and Deyber's paper, coming later, presumably em- 

 bodies the essence of Pupin's generalizations. 



During the same year other researches appeared from the hands 

 of Ramon y Cajal (20 and 21) which have a bearing on the general 



